Completely erasing epigenetic marks
By Shubhankar Kulkarni on Jul 27, 2020
Question: How do we completely erase the epigenetic marks from the cells during reprogramming?
Direct reprogramming (avoiding dedifferentiation and redifferentiation) was shown to preserve the aging phenotype by increasing factors involved in cellular senescence (p53, p21, and p16).  Examination of the iPSC methylome showed that they retain donor-age and tissue memory. They have different teratogenic, hematopoietic, and osteogenic potential based on their tissue of origin. Certain CpG sites preserve age-specific methylation pattern even after 100 passages following reprogramming.  These findings suggest that reprogramming does not fully bring differentiated cells to their ground state, but rather approximates it.
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