The Genetic Adaptation of the Sea Women

Off South Korea's Jeju Island, women as old as 70 and even older free dive up to 60-feet three or more times a week to collect seafood -- abalone, sea urchins, and seaweed -- to eat or sell. Known as Haenyeo, or sea women, many began diving as children, continued through pregnancy, and resumed just days after childbirth. Though the tradition is fading, its impact may still be apparent in their genes. And from them, scientists may have discovered a key to reducing strokes and high blood pressure.

A study published in Cell Reports by Dr. Melissa Ilardo of the University of Utah and her team found that Jeju Islanders carry a genetic variant that helps regulate blood pressure during diving. This adaptation likely developed through natural selection over centuries and may help prevent conditions like stroke and preeclampsia.

The study suggests this genetic trait became more common through evolutionary pressure: pregnant women lacking the variant may have developed complications and died. At the same time, those with it survived and passed it on.

Similar studies have examined other adapted populations, like Indonesia's Bajau divers with enlarged spleens and Tibetans with altitude adaptations. Such research has led to significant medical advances, including the development of PCSK9 inhibitors for lowering cholesterol.

If you're an active free diver, unless you have the gene, don't expect the benefits the Sea Women have developed, but if your children, grandchildren, and a few more generations follow, maybe down the line, some long-life genes will show up in them, too.

Read the study here: www.cell.com/cell-reports/fulltext/S2211-1247(25)00348-1