Ezhavas showed more genotypic resemblance to the Jat Sikh population of Punjab and the Turkish populations than to East Asians, indicating a paternal lineage of European origin, according to a study on Deoxyribo Nulceic Acid (DNA) profiling of Kerala population conducted by a three-member team of experts attached to Department of Biotechnology and Biochemical Engineering at Sree Budha College of Engineering (SBCE) at Pattoor near Pandalam.
The study was conducted by Dr Seema Nair.P, Head of the department of Biotechnology and Biochemical Engineering at SBCE, Aswathy Geetha and Chippy Jagannath of the same department with the help of a group of students.
The study report has already been published in the Croatian Medical Journal (Croat MedJ), giving it an international exposure recently.
According to Dr Seema, the study has completely analysed the short tandem repeat (STR) profile of Y-chromosomes in male blood samples.
Whole blood samples were collected from 104 unrelated healthy men of the Ezhava population over a period of one year from October 2009.
Genomic DNA was extracted by salting out method and all samples were genotyped for the 8 Y-STR loci by the AmpFiSTR Y-filer PCR Amplification Kit. The haplotype (and allele frequencies were determined by direct counting and analyzed using Arlequin 3.1 software, and molecular variance was calculated with the Y-chromosome haplotype reference database online analysis tool, www.yhrd.org.
Haplotype is a combination of DNA sequences (alleles) at different places (loci), she said.
As many as 98 of the 104 haplotypes examined were found unique ones.
“Out of the 104 haplotypes, 10 were found identical to the Jat Sikh population of Punjab which is the greatest number among the Indian populations, and 4 to the Turkish population, which is the greatest number among the European populations. It further clarifies that the Ezhavas were genetically more similar to the Europeans (60%) than to the East Asians (40%),’’ the study report said.
“Due to the geographical position of the Indian Peninsula between Africa, the Pacific, and west and east Eurasia, different populations have moved through its territory. This is why ethnic Indian population shows enormous cultural, linguistic, and genetic diversity. The long seacoast of Kerala on the southern-most part of India has provided a gateway to India for many Asian, European, and Srilankan missionaries and traders. Non-tribal communities of Kerala, as shown by a human leukocyte antigen (HLA) analysis, were influenced by Dravidian, Indo-European, and East Asian gene pools.’’
According to the allele frequency distribution, the Ezhava population of Kerala has got features of European, Central Asian, and East Asian gene pools. Mitochondrial DNA studies also validated the presence of two distinct, eastern and western Eurasian-specific lineage groups in India, suggesting that there were at least two separate migration events to India, says the study report.
Dr Seema claims that this is the first report on the Y-STR profile in Kerala population. The Ezhava population was compared with other Indian populations and with selected world populations in order to investigate the pattern of paternal contributions, she adds.
According to Dr K. Sasikumar, chairman of Sree Budha Education Society who was the driving spirit behind the project, the data made available through the SBCE study would be of great help in developing unique genetic fingerprints or a DNA Barcode for personnel identification, forensic analysis, etc. The study has got much relevance as genetic fingerprinting can also help us a lot in predicting our future health, he said.