By studying centenarians, their children, and controls, researchers led by Yousin Suh have found a potential role for insulin growth factor one in human longevity. The scientists screened IGF1 and the IGF1 receptor genes in their study population and found a gender-specific effect. Female centenarians, as they report in PNAS, are more likely to have a heterozygous mutation in the IGF1 receptor gene that results in an altered IGF signaling pathway.