<p>Emmanuel Mignot explains how a variant of an immune system gene might protect some people against neurodegenerative disease.</p>

Skeletal records and gender bias

Welcome to Science Sessions, the PNAS podcast program. Listen to brief conversations with cutting-edge researchers, Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in PNAS, plus a broad range of scientific news about discoveries that affect the world around us.