I'm a stem cell biologist and I can tell you that organoids have changed my field of research. As explained in the video, we make organoids by providing stem cells with different molecules so that they undergo certain aspects of development. For example, we can make brain organoids which mimic parts of the brain (I made a video about them). Brain organoids are tiny and not as complex as real brains but they help us to understand brain diseases and have recently been used to explain how schizophrenia arises!
Yeah, I always found it funny that people believed it could be simple Mendelian trait, 2x2.... When in real life we can see so much complexity first hand... My mother has eyes that change colours, sometimes it's green (for example, when she's at the beach) and sometimes it's more yellowish, sometimes it gets more orangish... And at the same time I'd see how I mixed my parents eye colours: my father has really dark brown eyes (now with age it's starting to look blue, hehehe, just like his mother's irises have almost completely been covered with arcus senilis and now it looks like she has light grey eyes) then I have this middle hue of brown... But my brown eyes are slightly lighter than my sister's eyes...
Well this was known, the squares are more of a theoretical thing to help people understand the most simple form of inheritance. Problem is that that’s now how it’s taught in schools.
@@faramund9865 they can still teach the same Mendelian inheritance and method of predicting outcomes with those squares with other traits, like the ABO blood type system, haemophilia, etc... Kids will learn the method the same way, but not be trying to predict eye colours of babies, because that's too complicated for high school... Also, like it was mentioned here in other comments, many babies are born with one eye colour and then after a few years it changes to another and then it becomes stable, just like hair: many babies are blond and then their hair grows darker with age...
IIRC, long ago in the late 80s, my highschool bio teacher taught us that the pigment which accounts for most of the "brown" in brown eyes was simple mendelian, but "not brown" was much more complicated as well as some more complicated but less common ways to end up with brown. Which is pretty much still correct.
I got like a blue-grey-yellow hazel. It's a nice colour, but definitely not very similar to any close family. Genes are fun. EDIT: I just found out from another comment and further googling that I have central heterchromia, which I had never heard of prior to this. I'm having a moment here. Apologies for any derailing.
@@MurdocsMinion my nephew (we're black and I and my siblings and parents have eyes ranging from light brown to deep brown. Some people say my eyes look like a deep maroon color) but anyways my nephew's hazel eyes switches from deep slate blue olive green and smoky brown and gray all the time. He mother's hazel eyes go from forest green light brown and goldish Yellow. I think its neat and cool how eye color genes work.
True! My mom has hazel eyes with small flecks of gold. They're really pretty! Meanwhile my eyes are a sort of deep sea green/blue that shifts toward more green or blue depending on the light and my surroundings. Genetics really are neat!
If I could remember who was my biology teacher, I would rub this video in their face because they told me that what they taught me was accurate and my concern about shades of eye color wasn't real.
I have a yellow/light brown spot in my otherwise green-grey-blue (the colour is mixed) eyes. Especially in one eye. It's cool because in some light the yellow mixes with the bluish colour and then that eye looks really green while the other seems blue in comparison, so it seems like my eyes were different colours, while in fact it's an optic illusion.
I'm mixed Eurasian. I have hazel eyes despite my mother having dark brown eyes and my dad has blue eyes. Never understood why when I learned genetics in biology years ago.
My eyes have green, blue, and light brown in them. Usually they just look grey unless you're really up close, but, depending on lighting they can look green, blue, or even hazel
My eyes are pale grey blue with a yellow ring and brown specks but they look grey in my opinion. Some people say my eyes are green some say they are blue. Its always a bit complicated when peole ask me what eyecolor I have...
@@sinceritii3846 I had the same problem with difficult to determine color, but I recently found out I'm more green eyed, and here's why: You can make eyes stand out and look their colour more strongly by putting on the right eyeshadow. Blue eyes are supposed to look more blue when you wear blue or orange eyeshadow while green eyes pop with green or purple eyeshadow. When I put on blue eyeshadow my eyes just look greyish. But when I add green or purple my eyes definitely seem to take on a pretty green tint. That means my eyes are more green than blue even if it looks a bit ambiguous without eyeshadow. From what I could find, I think that if your eyes are really grey they will look bluish with blue eyeshadow and greenish with green eyeshadow (or ignore both), while eyes that lean in one direction will clearly be more affected by that colour. So now I get to be proud of my green eyes rather than reply "i wish I knew".
Leslie Fish once posted some of her own research into the genetics of eye color and coat color in domestic cats, and it's ridiculously complicated. (Including why only female cats can have tortoiseshell fur coloration.)
Unless they have Klinefelter syndrome, which results in a male person or animal having two or more X chromosomes in addition to a Y. A friend of mine has a male calico with it, since that's the only way for a male cat to be calico or tortoiseshell; we went over it in my genetics class, and it actually explained a lot about that cat.
I knew the DNA sites needed more work a few years ago. GEDcom said I had green eyes. Mine are amber. Those are both rare colors, but there's a huge difference between the two. I'm glad to hear that they're discovering more alleles.
I mean if you can find the pigment genes for things like red and purple in birds or another animal and implant them in someone (a hard thing to do) you could invent some new ones.
@@jasonreed7522 yeah but the fact is feathers and eyes are very different and many organic pigments arent pigments at all, rather are structural colours :( so unless you're albino I dont think we will be getting purple eyes any time soon
My broad family has a tendency to make blond and blue eyed babies that turn into brunettes with greens and hazel eyes. Except 1 who was born brunette and blue eyed, and grew to be blond and blue eyed!
So, basically, you're undergoing metamorphosis. But yeah, I know what you mean. When we were very young, my brother and I have had hair so blond it was almost white in the summer. Now, beyond 30, both our hair is almost black (resp. black streaked with premature strands of gray in my case).
well it is also in the genes, and the change is because some genes activate as we get older, so a lot change hair color when they grow up, and/or changes shades in their eye color :) myself also had almost blonde hair as a child with light blue eyes. now i got dark brown hair with grey eyes, and my beard got a red shine on top of the color of my hair. :)
My brother was born with almost black hair, which then turned blond around age 2, and slowly darkened over a few years to become properly brown, while his eyes went from blue to green. Meanwhile, I've always been a brunette with brown eyes 🙃
I have brown eyes but I’m told by a lot of people that when the light catches my eyes the color of my eyes look like a red brown, I think it’s pretty dope that the color of my eyes are slightly red, my mom has hazel eyes and my dad has green eyes btw, my older brothers eyes change from grey, blue, to green under different lightings (and I mean really vibrant ocean blue and like forest green)and my nana also has one blue eye and one brown.
My eyes are blue with light light brown in it.(Central Heterochromia) Makes them look gray in some light for some reason. Usually don't know what to put on forms or use on doll makers where I can only pick one color
Same! My eyes are blue grey with a yellow ring in it and brown specks. They can look grey blue or green depending on the light. I never know what to write on forms when it comes to eye color
In most light my eyes are your typical warm dark brown where you can barely see the pupil, but out in natural sunlight my eyes brighten to more of a hazel color. I literally have both of my parents' eye colors. Oh and if it reflects right my eyes turn gold o3o.
As a person whose eye course is hmm *complicated* - I really appreciate the simple acknowledgement that eyes are MORE than brown, blue, green etc - mine *CHANGE* - sometimes they're grayish, greenish (with clothes & makeup can enhance this) - blueish/brownish - known this since I was a kid - (now in my late 40s) - when it comes up with passport applications - never ever know what to put down
I remember when I was a kid I learned that a blue eyed parent and a green eyed parent could not have a brown eyed kid and that always stressed me out because that is my situation with my biological parents. I’m glad we’re past the simple explanations of eye color and the other genes that can explain this have been identified!
One eye color gene does seem to follow that inheritance pattern. How dominant an allele is doesn’t necessarily mean it’s more common, though. Type O blood is recessive to both the A and B alleles, yet it’s the most common blood type in the world.
Yes the classic brown eyes dominant over blue classic Punnet square is wrong. Geneticists have known this for years and years and you can see it in your own family. The truth is that there are some eye colour genes where the blue tends to dominate over brown. There are multiple genes all expressing something and the final mix of everything interacting together gives you your final eye colour. Also, simple dominant and recessive expression is not the whole picture, it can be way more complicated. I wish schools the world over would stop teaching the outdated model.
Organoid tear glands sounds like a perfect solution for my elder sister's dry eye problems. Ever since she lasered her eyes her tear glands haven't worked properly. Dry eyes are a huge discomfort.
I always found genetics to be fascinating. In particular, I thought eye and hair color were interesting because there are so many varieties in even just one general color. I loved learning about it in school, but to think of the advancements in genealogy from then is crazy!
People with William's Syndrome often have green or blue or hazel eyes. Brown is uncommon in any shade. Williams Syndrome people have irises often described as "lacy". Their bodies don't make as much of the protein elastin. This protein is responsible for many organ functions including eye development. There may be a coronation between elastin production at an early stage and eye color/pattern. 😁
The entirety of my maternal grandpop's irises went from brown to blue as he aged on in years. I'm hoping I inherited those genes. So far more hazel than brown, with some arcs of green contraction furrows. I still wear sunglasses and get regular eye exams, of course. Not taking any gambles on my vision for the sake of aesthetics.
They probably will. It’s just the eye losing pigment like the graying of hair. Blue/gray eyes don’t have pigment, green has a little and the color comes from how light bounces off the structure of the eye tissues. My husband had dark brown eyes when we met, now they’re closer to hazel.
I think you might be talking about arcus senilis... In your grandpa's eyes... It grows from the outer rims with age, but just in some people... I think it's genetic, my father has thin light grey rings around his dark brown eyes and his mother has so thick arcus senilis that now her eyes look blue
Arcus senilis only affect the appearance of the eye, it doesn't influence the vision, maybe that's why people don't talk about it much, because it's nothing to worry about..
@@derfelkardan7369 I had looked into arcus senilis back when I first researched and it didn't explain it on its own. The entirety of Pop-pop's irises gradually turned blue, not only a ring around the outer edges. And the structures and detail of the irises were still completely visible, unlike in arcus senilis where the deposits cover it. I definitely find arcus senilis quite interesting and unique an effect, and was so relieved to learn that it was harmless! Thank you for bringing the suggestion in case I hadn't heard of it!
@@derfelkardan7369 Omg I always thought my nana had cataracts but with a search this is the cause of her blue ring on her eye. I think she does have cataracts or something that she does have to get tested with something involving needles in or near her eyes idk lol. But now I can compliment them and say it’s actually just a cool thing you get with age not her cataract idk.
My mom has blue eyes, my father has green eyes. Depending on the light, I can see both blue and green. However, if light from a camera hits them correctly, they look bright, light blue.
I think this is a prime example of that we should be vary of "facts". Not that we should be overly skeptical about established truths, but we shouldn't be dogmatic about anything that involves complex processes and systems. Being aware that most things probably have nuance and non-simple answers is so important for actually understanding the world, problems we encounter, and how we can solve it and what trade-offs we make.
My daughter has green eyes with a couple of brown for a at the bottom of her left. 3 other kids I've noticed have the same dots on the same side. My eyes are blue, but my mum's eyes and all her family's were bright green, my daughters dads are hazel green... I think it is the hazel that caused the dots. And the green started as a hidden yellow behind her baby blues. Also, people think she has brown eyes as she doesn't open them wide enough for light to get to them.
My father had three colored eyes, but not mixed together. One eye was one color, the other eye was two colors divided vertically. Some years ago, saddened I could not remember the details, I asked his brother, but neither of us could even remember which was the solid color.
That's probably a form of heterochromia. It is characterized by having two or more different colours in your iris. In my case my eyes are literally two different colours. Blue and green respectively
@@Ikajo Central heterochromia. Thanks! I didn't knew it existed! Interestingly, I have a friend who has the opposite; brown eyes with a blue line around the iris. I found a photo that is similar to my eyes. i.pinimg.com/originals/2c/fb/16/2cfb165f653a85a8a9af890c3a4c8f04.jpg
@@MurdocsMinion It is a form heterochromia 🙂 you can also have eyes with a different colour each. That's how it is for me. When you have two different colours in both eyes it is also heterochromia.
@@Ikajo I always thought heterochromia was only when a person has two diffrent colored eyes, but I have leaned something new today, thanks! I guess I have a form of heterochromia then. I have grey blue eyes with a yellow ring and light brown specks
@scishow I have partial aniridia, more rare than aniridia in general, especially since I have no history of it. I have some color in my eyes, maybe half of the color of others in diameter. I also have tiny slivers of my iris missing, It kinda looks like the back end of a hole punch... or the little pieces in the collector of a 3 hole punch, the tiny slivers. I live in the city so I have never really driven, I have pretty good eyesight so I am grateful for no pressure. I look messed up to most people, security follows me in stores and I wont get served at a new bar. My eyes are squinty esp in bright sun / complete (light) cloud /overcast skies, I get the biggest squint headaches with overcast and bright fresh snow. I hear you can get an artificial but you have to get your lenses out and then use drops for the rest of your life ... I'm gonna hold off jic.... I can always send you a pic of my eyes if you guys are thinking of other cool pax 6 ideas lol... really enjoy all the stuff here and across the channels. If I can make annoying dj requests, my ideas would be dna things like 'the dna universe' exploring all kinds of weird stuff, chromos and more ...it would be cool to see across animals spectrums what dna to eye vs gills does in a variety of animals my other last request is anything about appalachian geology and paleo things too .... sometimes I wish there was a native series with old tribes and other naturalists.
It's obviously very complicated. For some people, when you look at their eyes you can actually see that it's a mix of different colors, like blue with a yellowish ring, or brown around the pupil and green above, or multiple shades of brown with some redish or honey color. I myself have green-greyish eyes with some yellow on top of the pupil, my mother have sky blue and my father a light shade of brown.
my eyes are a bit brown at the centre and blue/green-ish around that. Haven't found others with the same thing, but then again i haven't really been looking for it
@@dr.blockcraft6633 That's it! My dad, brother, sister and I have it too, with a circle of green around the iris and a circle of brown around that. In our family, it seems the heterochromia is dominant. I hope they take a look at the various heterochromias out there, in light of the new genes they've found. That might tell them even more about the genes involved in making the eye.
At 4:50... "there is always something more to understand"..... Yep! 50 more genes controlling eye color! Who would have thought! Keep the videos coming. They are great!
My first born's eyecolor went against everything I had learned about eyecolor. They look like someone put my eyecolor (green/blue/grey) and his father's (hazel) together, and then gave it a very gentle stir so the colors didn't mix, they just sort of swirled together a little bit. I think they look like beautiful Mother Earth, because there's blue, green, and golden brown spots.
I never thought eye color was a mendelian trait. Not because I had any particular reason to but I'm pretty sure I was told in high school biology that traits like height and eye color were affected by many genes and that seemed to make sense since we all know that eyes are pretty much like snow flakes in that there are an extremely wide variety.
My eyes were a dark blue till I was about 3, then they darkened to a brown, then they lightened to a hazel. Even though after I cry or depending on what I wear they look more green.
My eyes are a combo of blue/green seemingly shifting colors with a small amount of hazel around my pupil! Ppl always ask why my id says hazel and I’m like well that’s what they told me to put
Maybe an anomaly with tri-colour eyes, blue on the outer edge, green in the center, and flecks of hazel or wheat across the iris. With both parents having deep brown eyes. Early 2000's science class taught me with the classic Pennet square that somebody was cheating. 😅
I think that my eye color has changed slightly as I have gotten older. When I was young, I had reasonably uniformly brown eyes. Now they are a lighter hazel with more variations in color.
It’s always amusing to me when genetic analyses predict I have either brown or hazel eyes. My actual eye color is blue and apparently rare for the majority of participants who share similar genes/SNPs.
My mom and I both have central heterochromia of the type usually associated with hazel eyes, and I can state that in my family it does look like a simple situation- mother and daughter with hazel eyes and the recessive gene for blue, father and son with blue eyes. It's not. My eyes are amber around the center and green around that, with a thick dark ring around the border. As for why eyes can be several different colors at the same time? Rayleigh scattering.
My mom has green eyes and had blonde when she was a kid, now brown hair. My dad brown eyes and blonde hair growing up, now brown. I have eyes that go to from dark brown to green with blonde hair that's turning red.
Every member of my family has a different shade of green eyes. I remember learning the overly simplistic blue/brown model and thinking there's got to be a lot more to this!
They’re probably going to be looked at in a future study to add to this body of research, as will populations from other parts of the world that weren’t sampled for this study.
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ok I'll do that *wink meme*
i do enjoy brilliant, when I need a subscription I will use your link
So,...what you are saying is: Candy-colored eyes are possible?
Can you do a video of indigestion please, if you have tho that's ok too
👀
I'm a stem cell biologist and I can tell you that organoids have changed my field of research. As explained in the video, we make organoids by providing stem cells with different molecules so that they undergo certain aspects of development. For example, we can make brain organoids which mimic parts of the brain (I made a video about them). Brain organoids are tiny and not as complex as real brains but they help us to understand brain diseases and have recently been used to explain how schizophrenia arises!
Fascinating
That's very interesting
Papers on the schizophrenia pretty please?
What causes schizophrenia then?
Also curious about the schizophrenia stuff.
I always figured it was waaaay more complicated that the good ol' 2x2 punnet squares
Yeah, I always found it funny that people believed it could be simple Mendelian trait, 2x2.... When in real life we can see so much complexity first hand... My mother has eyes that change colours, sometimes it's green (for example, when she's at the beach) and sometimes it's more yellowish, sometimes it gets more orangish... And at the same time I'd see how I mixed my parents eye colours: my father has really dark brown eyes (now with age it's starting to look blue, hehehe, just like his mother's irises have almost completely been covered with arcus senilis and now it looks like she has light grey eyes) then I have this middle hue of brown... But my brown eyes are slightly lighter than my sister's eyes...
Yep, just hazel & the origin of blue should have been enough indication that there was secret depths to that.
Well this was known, the squares are more of a theoretical thing to help people understand the most simple form of inheritance.
Problem is that that’s now how it’s taught in schools.
@@faramund9865 they can still teach the same Mendelian inheritance and method of predicting outcomes with those squares with other traits, like the ABO blood type system, haemophilia, etc... Kids will learn the method the same way, but not be trying to predict eye colours of babies, because that's too complicated for high school... Also, like it was mentioned here in other comments, many babies are born with one eye colour and then after a few years it changes to another and then it becomes stable, just like hair: many babies are blond and then their hair grows darker with age...
IIRC, long ago in the late 80s, my highschool bio teacher taught us that the pigment which accounts for most of the "brown" in brown eyes was simple mendelian, but "not brown" was much more complicated as well as some more complicated but less common ways to end up with brown. Which is pretty much still correct.
Make senses because of all the different shades of hazel eyes out there.
I love my shade of hazel, reminds me of peanut butter.
I got like a blue-grey-yellow hazel. It's a nice colour, but definitely not very similar to any close family. Genes are fun.
EDIT: I just found out from another comment and further googling that I have central heterchromia, which I had never heard of prior to this. I'm having a moment here. Apologies for any derailing.
@@MurdocsMinion my nephew (we're black and I and my siblings and parents have eyes ranging from light brown to deep brown. Some people say my eyes look like a deep maroon color) but anyways my nephew's hazel eyes switches from deep slate blue olive green and smoky brown and gray all the time. He mother's hazel eyes go from forest green light brown and goldish Yellow. I think its neat and cool how eye color genes work.
True! My mom has hazel eyes with small flecks of gold. They're really pretty! Meanwhile my eyes are a sort of deep sea green/blue that shifts toward more green or blue depending on the light and my surroundings. Genetics really are neat!
Hazel is not a shade. It is 2 different colors. It is specifically having stripes of green and brown.
If I could remember who was my biology teacher, I would rub this video in their face because they told me that what they taught me was accurate and my concern about shades of eye color wasn't real.
people who got them tricolor iris OCs on tumblr: my time has come
I mean I have bicolor irises so it isn't that far out of the realm of possibility
I have a yellow/light brown spot in my otherwise green-grey-blue (the colour is mixed) eyes. Especially in one eye. It's cool because in some light the yellow mixes with the bluish colour and then that eye looks really green while the other seems blue in comparison, so it seems like my eyes were different colours, while in fact it's an optic illusion.
@@ingridc0ld central heterochromia?
My brown eyes have been getting green around the edge for some years now for some reason
My eyes are 3 colors for real.
I feel like they specifically mentioned The Fault in Our Stars because Hank Green is John Green's brother
No doubt
Considering he's wearing a pizza Hank shirt...
Yea they've mentioned his book like two dozen times on the channel it's free advertising and it's getting pretty old by now
@@MrPepelongstockings helping family doesn't get old.
@@TragoudistrosMPH facts also that book highkey makes you cry
I'm mixed Eurasian. I have hazel eyes despite my mother having dark brown eyes and my dad has blue eyes. Never understood why when I learned genetics in biology years ago.
Shouting out his brothers book was so cute
So, the first artificial human we create will be able to cry. Good!
"New blood joins this word and quicly he's subdued..."
All those moments will be lost in time, like tears in rain.
@@ethan-loves brilliant. perfection.
"HA HA HA HA HA, THE LAST HUMAN IS ELIMINATED! FINALLY! ALSO WHY MY OPTICAL BALLS ASSEMBLY ARE GENERATING FLUID?"
And cry it shall
My eyes have green, blue, and light brown in them. Usually they just look grey unless you're really up close, but, depending on lighting they can look green, blue, or even hazel
Same! Minus the brown.
My eyes are pale grey blue with a yellow ring and brown specks but they look grey in my opinion. Some people say my eyes are green some say they are blue. Its always a bit complicated when peole ask me what eyecolor I have...
@@sinceritii3846 I had the same problem with difficult to determine color, but I recently found out I'm more green eyed, and here's why: You can make eyes stand out and look their colour more strongly by putting on the right eyeshadow. Blue eyes are supposed to look more blue when you wear blue or orange eyeshadow while green eyes pop with green or purple eyeshadow. When I put on blue eyeshadow my eyes just look greyish. But when I add green or purple my eyes definitely seem to take on a pretty green tint. That means my eyes are more green than blue even if it looks a bit ambiguous without eyeshadow. From what I could find, I think that if your eyes are really grey they will look bluish with blue eyeshadow and greenish with green eyeshadow (or ignore both), while eyes that lean in one direction will clearly be more affected by that colour.
So now I get to be proud of my green eyes rather than reply "i wish I knew".
@@judith769 Thanks for the tip! I'll test that out
ive had people tell me ive had green eyes and grey eyes. i have pale blue eyes with a yellow ring lol
In my undergrad biology courses back in the early 90s we were told that eye color was complex and non-Mendelian in nature.
Leslie Fish once posted some of her own research into the genetics of eye color and coat color in domestic cats, and it's ridiculously complicated. (Including why only female cats can have tortoiseshell fur coloration.)
Unless they have Klinefelter syndrome, which results in a male person or animal having two or more X chromosomes in addition to a Y. A friend of mine has a male calico with it, since that's the only way for a male cat to be calico or tortoiseshell; we went over it in my genetics class, and it actually explained a lot about that cat.
I knew the DNA sites needed more work a few years ago. GEDcom said I had green eyes. Mine are amber. Those are both rare colors, but there's a huge difference between the two. I'm glad to hear that they're discovering more alleles.
At first I thought it said we found new eye colors. I'm a little heartbroken ☹️☹️
Well, there are always finer gradations in the shades of brown to be identified, I guess.
my eyes are boring brown :( I wish I had cool eye colors
I mean if you can find the pigment genes for things like red and purple in birds or another animal and implant them in someone (a hard thing to do) you could invent some new ones.
@@jasonreed7522 yeah but the fact is feathers and eyes are very different and many organic pigments arent pigments at all, rather are structural colours :( so unless you're albino I dont think we will be getting purple eyes any time soon
@@Gwagwa333 we have a leg up on evolution and genetics: colored contacts (but i dont wear contacts lol)
Love the shout out to your brothers book!
My eyes have a darkish grey blue outer ring, pale yellow with a red orange flare around the pupil
I just say my eye are a solar eclipse
That is so cool!
My eyes are a mix of green and blue but it looks kinda grey lol
Same but light wood around pupil with green and aqua blue rim
@Eastern fence Lizard no nopenopenopenopenopwnope
Mine is a sunflower in a green-blue tropical sea
I love how Hank just drops his brother's book into the conversation and doesn't acknowledge that it's his brother's book
My broad family has a tendency to make blond and blue eyed babies that turn into brunettes with greens and hazel eyes. Except 1 who was born brunette and blue eyed, and grew to be blond and blue eyed!
So, basically, you're undergoing metamorphosis.
But yeah, I know what you mean. When we were very young, my brother and I have had hair so blond it was almost white in the summer. Now, beyond 30, both our hair is almost black (resp. black streaked with premature strands of gray in my case).
well it is also in the genes, and the change is because some genes activate as we get older, so a lot change hair color when they grow up, and/or changes shades in their eye color :)
myself also had almost blonde hair as a child with light blue eyes.
now i got dark brown hair with grey eyes, and my beard got a red shine on top of the color of my hair. :)
@@lonestarr1490 Yeah, it's the usual pattern that children with blonde hair grow up to have darker. Natural blond hair in adults isn't as common
My brother was born with almost black hair, which then turned blond around age 2, and slowly darkened over a few years to become properly brown, while his eyes went from blue to green. Meanwhile, I've always been a brunette with brown eyes 🙃
I did the same thing! I was born with dark brown hair, apparently, and by the time I hit a year, it had gone blond. Been that way ever since.
When genetic engineer is here in full swing, i'll make my eyes red like a Sith Lord.
You'll probably have to make yourself immortal like Palpatine as well.
In my family, we have completely different eye colors. My mom has brown eyes, my dad has green eyes, my brother has blue eyes, and I have hazel eyes.
Paternity test time!
@@unholy7324 no
I have brown eyes but I’m told by a lot of people that when the light catches my eyes the color of my eyes look like a red brown, I think it’s pretty dope that the color of my eyes are slightly red, my mom has hazel eyes and my dad has green eyes btw, my older brothers eyes change from grey, blue, to green under different lightings (and I mean really vibrant ocean blue and like forest green)and my nana also has one blue eye and one brown.
My eyes are blue with light light brown in it.(Central Heterochromia) Makes them look gray in some light for some reason. Usually don't know what to put on forms or use on doll makers where I can only pick one color
Same! My eyes are blue grey with a yellow ring in it and brown specks. They can look grey blue or green depending on the light. I never know what to write on forms when it comes to eye color
In most light my eyes are your typical warm dark brown where you can barely see the pupil, but out in natural sunlight my eyes brighten to more of a hazel color. I literally have both of my parents' eye colors. Oh and if it reflects right my eyes turn gold o3o.
Wow! The old phrase cry me a river suddenly has a whole new meaning.
You can't fool me. Organoids are special Zoids that can augment the abilities of other Zoids.
3:40 Those are some seriously beautiful eyes.
It's so sweet how Hank shouts out his brothers book whenever he can
If you can't study your own tear glands, store bought is fine...
if you cant grow your own tear glands, store bought is fine
Yep - try the Pharmacy section at Walmart. 😖
As a person whose eye course is hmm *complicated* - I really appreciate the simple acknowledgement that eyes are MORE than brown, blue, green etc - mine *CHANGE* - sometimes they're grayish, greenish (with clothes & makeup can enhance this) - blueish/brownish - known this since I was a kid - (now in my late 40s) - when it comes up with passport applications - never ever know what to put down
I remember when I was a kid I learned that a blue eyed parent and a green eyed parent could not have a brown eyed kid and that always stressed me out because that is my situation with my biological parents. I’m glad we’re past the simple explanations of eye color and the other genes that can explain this have been identified!
You are a robot hate to break it to you.
I knew I had the Sharingan in one eye and the Rinnegan in the other.
My eyes are two tone blue. Light blue inner with a dark blue ring on the outside. Just thought I'd share.
Josh
Me too, except the inner pastel blue has turned to pastel green over the years.
Brown on the outter part and green on the inner here.
Babe wake up, new eye colors just dropped
I've always wondered if it was a old wives tale that Brown eyes are more dominant than Blue. In my family it seems like the opposite.
One eye color gene does seem to follow that inheritance pattern. How dominant an allele is doesn’t necessarily mean it’s more common, though. Type O blood is recessive to both the A and B alleles, yet it’s the most common blood type in the world.
Yes the classic brown eyes dominant over blue classic Punnet square is wrong. Geneticists have known this for years and years and you can see it in your own family. The truth is that there are some eye colour genes where the blue tends to dominate over brown. There are multiple genes all expressing something and the final mix of everything interacting together gives you your final eye colour. Also, simple dominant and recessive expression is not the whole picture, it can be way more complicated. I wish schools the world over would stop teaching the outdated model.
Depends on which old wife you talk to. 😉
I like that you include what the broad scope of the research is.
"Fault in our stars, what's that?"
I'm sure John and Josh appreciate the plug.
Considering that the pigment part of the eye is muscle tissue, this might explain why some people's eyes can change colors.
The eye colour on the top-right corner is amazing, never seen anything like it irl.
It's a bit like mine! I have green eyes with brown freckles in them, and a rust-colored segment in one iris.
Organoid tear glands sounds like a perfect solution for my elder sister's dry eye problems. Ever since she lasered her eyes her tear glands haven't worked properly. Dry eyes are a huge discomfort.
I always found genetics to be fascinating. In particular, I thought eye and hair color were interesting because there are so many varieties in even just one general color. I loved learning about it in school, but to think of the advancements in genealogy from then is crazy!
Very cool. I think we knew we didn’t have the full picture and it’s great to see these researchers expanded our view. ;)
People with William's Syndrome often have green or blue or hazel eyes. Brown is uncommon in any shade. Williams Syndrome people have irises often described as "lacy". Their bodies don't make as much of the protein elastin. This protein is responsible for many organ functions including eye development.
There may be a coronation between elastin production at an early stage and eye color/pattern. 😁
The entirety of my maternal grandpop's irises went from brown to blue as he aged on in years. I'm hoping I inherited those genes. So far more hazel than brown, with some arcs of green contraction furrows.
I still wear sunglasses and get regular eye exams, of course. Not taking any gambles on my vision for the sake of aesthetics.
They probably will. It’s just the eye losing pigment like the graying of hair. Blue/gray eyes don’t have pigment, green has a little and the color comes from how light bounces off the structure of the eye tissues. My husband had dark brown eyes when we met, now they’re closer to hazel.
I think you might be talking about arcus senilis... In your grandpa's eyes... It grows from the outer rims with age, but just in some people... I think it's genetic, my father has thin light grey rings around his dark brown eyes and his mother has so thick arcus senilis that now her eyes look blue
Arcus senilis only affect the appearance of the eye, it doesn't influence the vision, maybe that's why people don't talk about it much, because it's nothing to worry about..
@@derfelkardan7369 I had looked into arcus senilis back when I first researched and it didn't explain it on its own. The entirety of Pop-pop's irises gradually turned blue, not only a ring around the outer edges. And the structures and detail of the irises were still completely visible, unlike in arcus senilis where the deposits cover it. I definitely find arcus senilis quite interesting and unique an effect, and was so relieved to learn that it was harmless!
Thank you for bringing the suggestion in case I hadn't heard of it!
@@derfelkardan7369 Omg I always thought my nana had cataracts but with a search this is the cause of her blue ring on her eye. I think she does have cataracts or something that she does have to get tested with something involving needles in or near her eyes idk lol. But now I can compliment them and say it’s actually just a cool thing you get with age not her cataract idk.
Do fish eyes really produce warped images like fish eye camera lenses?
And if they do, isn't it likely that their brain corrects for it?
My mom has blue eyes, my father has green eyes. Depending on the light, I can see both blue and green. However, if light from a camera hits them correctly, they look bright, light blue.
1:05 "I'll give you something to cry about!"
When he said "You can't make an organoid read TFIOS" I just stoppped and stared for a second
I was hopping for a bit more details about this but thanks for the video
1:14 'So instead of making an organoid read the fault in our stars'
Shameless brotherly promotion =D
One step away from introducing Red, Purple and other exotic eye colours in genes, huh?
Hank makes me cry tears of knowledge ;)
I have light blue eyes, one brother has hazel eyes, one has amber brown eyes, one has dark ocean blue eyes, and my sister has green eyes
I knew eye color was more complicated! Especially since I have multi colored eyes because of partial heterochromia
I think this is a prime example of that we should be vary of "facts". Not that we should be overly skeptical about established truths, but we shouldn't be dogmatic about anything that involves complex processes and systems. Being aware that most things probably have nuance and non-simple answers is so important for actually understanding the world, problems we encounter, and how we can solve it and what trade-offs we make.
I appreciate the color work on the word SHADES
I can't get enough of SciShow!
smooth promotion Hank... I love TFIOS, but Looking for Alaska is way more emotional for me.
My daughter has green eyes with a couple of brown for a at the bottom of her left. 3 other kids I've noticed have the same dots on the same side. My eyes are blue, but my mum's eyes and all her family's were bright green, my daughters dads are hazel green... I think it is the hazel that caused the dots. And the green started as a hidden yellow behind her baby blues. Also, people think she has brown eyes as she doesn't open them wide enough for light to get to them.
My father had three colored eyes, but not mixed together. One eye was one color, the other eye was two colors divided vertically. Some years ago, saddened I could not remember the details, I asked his brother, but neither of us could even remember which was the solid color.
Is that why I have a brown line around my pupils in my grayish-blue eyes?
That's probably a form of heterochromia. It is characterized by having two or more different colours in your iris. In my case my eyes are literally two different colours. Blue and green respectively
@@Ikajo Central heterochromia. Thanks! I didn't knew it existed! Interestingly, I have a friend who has the opposite; brown eyes with a blue line around the iris.
I found a photo that is similar to my eyes.
i.pinimg.com/originals/2c/fb/16/2cfb165f653a85a8a9af890c3a4c8f04.jpg
@@Ikajo Wait that's heterochromia?? I thought it was just a weird type of hazel eyes. I've got a yellow-brown line around my pupils. O.O
@@MurdocsMinion It is a form heterochromia 🙂 you can also have eyes with a different colour each. That's how it is for me. When you have two different colours in both eyes it is also heterochromia.
@@Ikajo I always thought heterochromia was only when a person has two diffrent colored eyes, but I have leaned something new today, thanks! I guess I have a form of heterochromia then. I have grey blue eyes with a yellow ring and light brown specks
@scishow I have partial aniridia, more rare than aniridia in general, especially since I have no history of it. I have some color in my eyes, maybe half of the color of others in diameter. I also have tiny slivers of my iris missing, It kinda looks like the back end of a hole punch... or the little pieces in the collector of a 3 hole punch, the tiny slivers. I live in the city so I have never really driven, I have pretty good eyesight so I am grateful for no pressure. I look messed up to most people, security follows me in stores and I wont get served at a new bar. My eyes are squinty esp in bright sun / complete (light) cloud /overcast skies, I get the biggest squint headaches with overcast and bright fresh snow. I hear you can get an artificial but you have to get your lenses out and then use drops for the rest of your life ... I'm gonna hold off jic.... I can always send you a pic of my eyes if you guys are thinking of other cool pax 6 ideas lol... really enjoy all the stuff here and across the channels. If I can make annoying dj requests, my ideas would be dna things like 'the dna universe' exploring all kinds of weird stuff, chromos and more ...it would be cool to see across animals spectrums what dna to eye vs gills does in a variety of animals
my other last request is anything about appalachian geology and paleo things too .... sometimes I wish there was a native series with old tribes and other naturalists.
Great suggestions. I’m glad you can enjoy RUclips!
I love this because I was so sad when my teachers couldn’t tell me how I got hazel eyes but could explain blue and brown
It's obviously very complicated. For some people, when you look at their eyes you can actually see that it's a mix of different colors, like blue with a yellowish ring, or brown around the pupil and green above, or multiple shades of brown with some redish or honey color. I myself have green-greyish eyes with some yellow on top of the pupil, my mother have sky blue and my father a light shade of brown.
I find it interesting that in the eye chart at 3:38, the participant with the green eye in the top right corner is wearing a contact lens.
my eyes are a bit brown at the centre and blue/green-ish around that. Haven't found others with the same thing, but then again i haven't really been looking for it
@@dr.blockcraft6633 That's it! My dad, brother, sister and I have it too, with a circle of green around the iris and a circle of brown around that. In our family, it seems the heterochromia is dominant.
I hope they take a look at the various heterochromias out there, in light of the new genes they've found. That might tell them even more about the genes involved in making the eye.
Always more to learn! ❤️
At 4:50... "there is always something more to understand"..... Yep! 50 more genes controlling eye color! Who would have thought!
Keep the videos coming. They are great!
My first born's eyecolor went against everything I had learned about eyecolor. They look like someone put my eyecolor (green/blue/grey) and his father's (hazel) together, and then gave it a very gentle stir so the colors didn't mix, they just sort of swirled together a little bit. I think they look like beautiful Mother Earth, because there's blue, green, and golden brown spots.
Thanks for this, I have had Sjogrens for over 30 years.
I love scishow so much, it reminds me how much I love science when school gets rough 💞💞
Nice plug for John's book
Ive been waiting for this
This also gives me hope that the time when robots will replace humans is never.
I have Hazel eyes, so, they don't know what they want to be... :P
I never thought eye color was a mendelian trait. Not because I had any particular reason to but I'm pretty sure I was told in high school biology that traits like height and eye color were affected by many genes and that seemed to make sense since we all know that eyes are pretty much like snow flakes in that there are an extremely wide variety.
That shout out to your brothers book was smooth
Interesting video!!!
My eyes were a dark blue till I was about 3, then they darkened to a brown, then they lightened to a hazel. Even though after I cry or depending on what I wear they look more green.
This is why I love science so much like nature it always changes
This explains why I have no idea what colour my eyes are. Somewhere in between blue and green but with a light brown tint in the centre
hank mentioning the fault in our stars was so cute
Thanks for the warning that _The Fault In Our Stars_ is a tear jerker. I shall now remove it from my to-read list.
One of my sons has brown eyes, the other son has grey eyes and my daughter has hazel eyes. My eyes are a mixture of green, amber brown and grey.
hank green referencing his brother book
love it
My eyes are a combo of blue/green seemingly shifting colors with a small amount of hazel around my pupil! Ppl always ask why my id says hazel and I’m like well that’s what they told me to put
My eyes are the same!
Same here
Can you do a video about 'limbal rings'? A pigmented line that separates the iris from the sclera, but not everyone has it.
1:14 Cheeky brotherly promotion 😏
Maybe an anomaly with tri-colour eyes, blue on the outer edge, green in the center, and flecks of hazel or wheat across the iris. With both parents having deep brown eyes.
Early 2000's science class taught me with the classic Pennet square that somebody was cheating. 😅
It’d be cool if we could naturally have purple or gray eyes.
Some Albino people have purple eyes, gray eyes have to do with collagen in the iris
4:08 Look, it’s the rare blue eyes white boy!
Subtle nod to his brothers book love it
I think that my eye color has changed slightly as I have gotten older. When I was young, I had reasonably uniformly brown eyes. Now they are a lighter hazel with more variations in color.
It’s always amusing to me when genetic analyses predict I have either brown or hazel eyes. My actual eye color is blue and apparently rare for the majority of participants who share similar genes/SNPs.
My mom and I both have central heterochromia of the type usually associated with hazel eyes, and I can state that in my family it does look like a simple situation- mother and daughter with hazel eyes and the recessive gene for blue, father and son with blue eyes. It's not. My eyes are amber around the center and green around that, with a thick dark ring around the border. As for why eyes can be several different colors at the same time? Rayleigh scattering.
My mom has green eyes and had blonde when she was a kid, now brown hair. My dad brown eyes and blonde hair growing up, now brown. I have eyes that go to from dark brown to green with blonde hair that's turning red.
Every member of my family has a different shade of green eyes. I remember learning the overly simplistic blue/brown model and thinking there's got to be a lot more to this!
3:40 top row, 3rd one from left...drugs...yep
I called it!
The study should have had people from africa
They’re probably going to be looked at in a future study to add to this body of research, as will populations from other parts of the world that weren’t sampled for this study.