A new study published in Cell Reports on May 2, 2025, reveals unique genetic traits in the Haenyeo, the women divers of Jeju Island, South Korea. These women are known for their remarkable ability to freedive to significant depths without any breathing equipment. The research indicates that these genetic adaptations contribute to their tolerance of cold water and their ability to regulate blood pressure during dives.
Researchers compared the genetics of 30 Haenyeo divers with those of non-divers from Jeju and mainland South Korea. The study found distinct genetic variations in the Jeju population, including a higher prevalence of a sarcoglycan zeta gene variant associated with cold sensitivity. Additionally, a variant of the Fcγ receptor IIA gene was more common in Jeju women, potentially aiding in regulating blood vessel response to inflammation and lowering blood pressure during dives.
These findings suggest that the Haenyeo's exceptional diving abilities are due to both training and genetic adaptation, making them the second known population of traditional breath-hold divers to have evolved for diving. The study highlights the importance of understanding these adaptations, which could lead to insights into treating conditions like hypertensive disorders and stroke.