Thanks for asking. Longer genes are obviously sequenced more number of times compared to shorter genes leading to biased expression data. To avoid this bias arising due to gene length, in normalization method like TPM, it is divided by gene length. This ensures precise normalization of gene expression and also fair comparison of expression levels of genes across different samples, which otherwise may result in blunders. Hope this answers your question.
Short and very informative. Great Work :-)
Thank you so much.
For the TPM, why do we divide by the gene length?
Thanks for asking. Longer genes are obviously sequenced more number of times compared to shorter genes leading to biased expression data. To avoid this bias arising due to gene length, in normalization method like TPM, it is divided by gene length. This ensures precise normalization of gene expression and also fair comparison of expression levels of genes across different samples, which otherwise may result in blunders. Hope this answers your question.