The old idea that looking at the maternal grandfather's hairline to predict whether a man will go bald is about half right, genetic researchers have found. The female X chromosome carries one baldness gene, but two studies have identified another gene that can be inherited from Dad. Guys with both markers are seven times more likely than men with neither to start losing it in their 40s, the Guardian reports.
"Baldness is a major cause of depression, social shyness and stigma for some people," said the lead researcher, "particularly those who go bald in their early years." Genetic factors account for most cases of male-pattern baldness, which affects around 30% of men by their 40s. For the 14% of the population that carries both baldness genes, the new findings could help identify those most at risk and let them start treatment early.
(More baldness stories.)