Thursday, September 08, 2005

BRCA1 variant   posted by gcochran @ 9/08/2005 04:20:00 PM

There is a new BRCA1 haplotype with a geographical distribution reminiscent of that seen in microcephalin and ASPM: the new variant is about 30k years old and considerably more common outside of sub-Saharan Africa (~55%) than inside (~20%) . BRCA1 has also been evolving unusually rapidly in the hominid lineage (like ASPM and microcephalin). It is suspected of having something to do with brain development, since it is highly expressed in neural stem cells and is functionally linked with microcephalin. Also, the high incident of BRCA1 mutations among the Ashkenazi Jews - as part of a complex of DNA-repair mutations - suggests that tweaking BRCA1 can affect cognition.