Srinagar, Apr 14: The first ever, landmark GenomeIndia Consortium report detailing the genetic makeup of nearly 10,000 Indians across 83 diverse populations, including the diverse populations in J&K, is out.
The preprint ‘An Atlas of Indian Genetic Diversity’ shows J&K population falls squarely within the Indo-European non-tribal (IE_NT) cluster, the dominant group scattered in northern India.
The study, posted on medRxiv in the last week of March provides the most detailed whole-genome sequencing data for India till date.
The report highlights the country’s immense genetic variation shaped by geography, language, history, and endogamy traditions among some populations.
The data analysis shows a clear north-to-south genetic cline: the northern populations have stronger affinities to ancestral northern Indian components, while the southern groups reflect more ancient indigenous ancestry.
A heat map of India, which is part of the report, shows sampling sites from 82-83 populations.
These sites are colour-coded by major ethno-linguistic groups – Indo-European (IE) majorly in northern and central India, Dravidian (DR) in southern India, Tibeto-Burman (TB) in northeastern, and some Himalayan areas, Austro-Asiatic (AA) which are often tribal communities.
The Northern non-tribal Indo-European (NT-IE) groups have generally been seen to have relatively fewer “private” or novel variants, in comparison with the isolated southern or tribal populations.
J&K, is included in the GenomeIndia sampling through collaboration with the Sher-e-Kashmir Institute of Medical Sciences (SKIMS), Soura.
The samples from the region were found to fall directly within the Indo-European non-tribal cluster.
This is the dominant group across northern India.
The key insights for J&K show Kashmir samples align with other IE-speaking populations in northern and central India.
The sample analysis reveals a mix of steppe-related ancestry, linked to ancient Indo-Aryan migrations and South Asian components.
This places Kashmir populations genetically closer to populations in Punjab, Haryana, and Uttar Pradesh.
Kashmir shares much of its genetic variation profile with other genetic variation profile with northern caste, non-tribal populations.
The preprint also looks at the genetic consequences of tradition of endogamy in many populations of India.
It utilises the Runs of Homozygosity (ROH), the long stretches of DNA that are identical on both chromosomes for this purpose.
These serve as a indicators for historical inbreeding and consanguinity.
The report states that “the IE_NT as a whole had limited ROH burden yet several populations had >70 percent individuals with FROH ≥0.01. This suggests that fine-scale sociocultural structures influencing cryptic-relatedness may exist even within these large, non-tribal communities.”
