Bipolar risk boosted by accumulation of rare versions of genes

Variants alter nerve cell activity, study suggests

bipolar graph

RISING RISK  People with bipolar disorder are more likely than others to have several rare versions of genes that control how much nerve cells fire. Width of the shapes in the graph indicate how many people in each group had a given number of rare gene types.

S.A. Ament et al/PNAS 2015

A buildup of rare versions of genes that control the activity of nerve cells in the brain increases a person’s risk for bipolar disorder, researchers suggest in a paper posted online the week of February 16 in Proceedings of the National Academy of Sciences.