Background

Human genome research has long been biased toward Western European populations. Since over 75% of genomic analysis data registered in global public databases is concentrated in populations of European ancestry, the genetic diversity of indigenous groups in Asia and Africa, with diverse ethnic backgrounds, has remained in a research blind spot.

In particular, the Indian subcontinent, home to over 1.4 billion people, has undergone unique genetic drift, having been divided into more than 4,500 linguistic, geographic, and socio-endogamous groups. The Gujarat region in western India, which served as a key coastal corridor during the expansion of early Homo sapiens from Africa into Eurasia, is considered a critical node in ancient migration routes.

However, due to geographic isolation and strict intra-community endogamy customs, the genomic information of indigenous tribal groups in this region has remained largely unidentified. As a result, despite the high frequency of unique recessive genetic diseases such as Sickle Cell Anemia (SCA), Beta-Thalassemia, and Glucose-6-Phosphate Dehydrogenase (G6PD) deficiency within these tribes, structural limitations existed in establishing precise diagnosis and treatment strategies.

Key Findings

An international collaborative research team, led by the Gujarat Biotechnology Research Centre (GBRC), completed Whole-Genome Sequencing (WGS) using high-depth Next-Generation Sequencing (NGS) technology for the genomes of 2,000 indigenous people residing in 17 tribal districts.

The researchers identified approximately 8 million new single nucleotide polymorphisms (SNPs) and structural variants through this whole-genome sequencing. More than 30% of these variants were confirmed to be unique variants not listed in the existing 1000 Genomes Project or the Human Pangenome Reference Database.

Population genetics analysis revealed that the genomic lineage of the Gujarat tribal people carries heavy genetic traces of the ancestral Eurasian migratory group that left Africa approximately 60,000 years ago and moved eastward along the southern coastal route. Compared to other Eurasian populations, they showed distinct differences in the ratio of gene influx from ancient Neanderthals and Denisovans.

In disease-related analysis, the frequency of the rs334 variant in the hemoglobin subunit beta (HBB) gene reached up to 18% in certain tribal groups, a figure comparable to high-risk regions in sub-Saharan Africa. Statistical evidence also confirmed that Mediterranean-type and geographically specific deficiency variants of the G6PD gene, associated with resistance to malaria infection, are fixed in a population-specific manner.

Significance and Outlook

This achievement marks a major milestone in addressing the imbalance of the global reference genome by securing large-scale genomic data from underserved non-European populations. It is regarded as having restored a key link necessary for reconstructing the settlement routes of human ancestors in Eurasia at the molecular level.

From a medical perspective, fundamental data has been secured to significantly improve the molecular diagnostic standards for the National Sickle Cell Anemia Elimination Mission being pursued by the Indian government. This also lays the foundation for developing customized diagnostic chips tailored to Korean and Asian populations that reflect unique variants.

However, the practical challenges faced by the researchers are also significant. Genetic data sovereignty must be protected and bioethical governance established to prevent the commercial misuse of genetic information in vulnerable indigenous communities. Follow-up studies expanding the analysis target to thousands of other tribal groups outside of Gujarat, beyond the statistical representativeness of the 2,000-person sequencing data, will be required to complete a true disease genome map for all of India.