Contact: Jules Asher NIH/National Institute of Mental Health
Caption: Our brains are all made of the same stuff. Despite
individual and ethnic genetic diversity, our prefrontal cortex
shows a consistent molecular architecture. For example, overall
differences in the genetic code (“genetic distance”) between
African -Americans (AA) and caucasians (cauc) showed no effect
on their overall difference in expressed transcripts
(“transcriptional distance”). The vertical span of color-coded
areas is about the same, indicating that our brains all share
the same tissue at a molecular level, despite distinct DNA
differences on the horizontal axis. Each dot represents a
comparison between two individuals. The AA::AA comparisons
(blue) generally show more genetic diversity than cauc::cauc
comparisons (yellow), because caucasians are descended from a
relatively small subset of ancestors who migrated from Africa,
while African Americans are descended from a more diverse gene
pool among the much larger population that remain