BHU-linked study finds milk-digesting gene variants in Himalayan communities

VARANASI: A team of 13 scientists from six Indian institutions, including Banaras Hindu University, has reported distinctive genetic variants linked to the ability to digest milk among communities of the Indian Himalaya.

For Varanasi, the work is another marker of the genetics research under way at BHU, whose Centre for Genetic Disorders took part alongside the University of Calcutta and the Centre for Cellular and Molecular Biology in Hyderabad. For the general reader, it offers a glimpse of how food habits and the human body shape one another over a very long time.

What the study found: The researchers examined DNA samples from Himalayan groups such as the Bhutia, Tamang and Sherpa and other communities of Tibetan origin, who have kept livestock and used dairy for centuries. According to the team, they identified three variants associated with lactase tolerance that had not been recorded in an Indian population before. The variant common in Europe and on the Indian plains was present only to a limited extent, while the main variant known from the Tibetan plateau appeared in good numbers. The samples were compared with genetic data from Indo-European, Dravidian, Austroasiatic and Tibeto-Burman language groups.

The researchers describe the pattern as gene-culture co-evolution: generations of reliance on milk in a harsh, high-altitude climate left a mark on DNA. A BHU scientist said the findings would also help in understanding ancient human migration, old trade routes and adaptation to high altitude.

The team is now preparing wider genome sequencing and clinical studies. Details are from the researchers' statements published by Hindustan and Amar Ujala on 14 November.