The first comprehensive genetic study of the populations in Himalayan region has suggested a common ancestry with intra-population sharing of genomes than in any other neighbouring groups of East Asian or South Asian.
An international team co-led by Kumarasamy Thangaraj of CSIR-Centre for Cellular and Molecular Biology (CCMB) and Gyaneshwer Chaubey from Banaras Hindu University (BHU)-Varanasi, along with scientists from Estonia, Israel, UK and Switzerland, studied DNA of 794 individuals belonging to 16 ethnic groups and published the research paper in prestigious scientific journal ‘Human Genetics’.
“Our high resolution analyses coupled with wider geographic coverage has revealed a distinct genetic trait of Trans-Himalayan populations, which could have originated due to its own novel genetic component and mixed at different degree with East and South Asian ancestries,” explained Kumarasamy Thangaraj, senior scientist, CSIR-CCMB.
Scientists analysed samples using mitochondrial, ‘Y’ chromosomal DNA markers among the ethnic groups of Changpa from Kashmir, Bhotia, Ban Raut from Uttarakhand, Sherpa Subba from Darjeeling and several populations from North East states to understand the genetic diversity of the region.
In addition to the uniparently-inherited genetic markers, authors have genotyped about 850,000 autosomal markers among 35 individuals belonging to four major populations of the region.
Himalayan mountain range in Asia separates the plains of the Indian subcontinent from the Tibetan Plateau spreading between 200 and 400 km with total area amounting to about 230,000 square miles (595,000 square km) and spans Jammu & Kashmir, Himachal Pradesh, Uttarakhand, Sikkim, Arunachal Pradesh, Assam and West Bengal with 42 languages being spoken.
“Massive sharing of genomes than in any other neighbouring groups suggested a common ancestry of the populations studied here,” said George van Driem, a renowned linguist from University of Bern, Switzerland. “Expansion of the Himalayan novel genetic component was followed by isolation by distance model in the east of Himalayas, but it showed an abrupt fall of this ancestry to the west of Himalaya,” said Prof. Chaubey, lead author and BHU Professor.
Himalayan populations study provides continuity in reconstructing the human evolutionary history of the Eurasians, according to Rakesh Tamang, Assistant Professor, Kolkata University.
CCMB Director Rakesh Mishra said such extensive studies on the Himalayan and adjoining populations were essential for a comprehensive reconstruction of the human evolutionary and ethnolinguistic history of eastern Eurasia.
