Genetic Diversity and Haplogroup Distribution of Three Ethnic Groups Tay, Thai, and Nung

The mitochondrial genome, with outstanding characteristics such as maternal inheritance, non-recombination and high mutation rate, is of great importance in population genetics and evolution research. To study the genetic diversity and the distribution of haplogroups of the Tai – Kadai language group, blood samples of 108 men from three ethnic groups Tay, Thai and Nung were collected. Total DNA extracted from blood samples was used for library preparation and whole mitochondrial genome sequencing using NGS. Comparing the obtained mitochondrial genome sequence with the RSRS (Reconstructed Sapiens Reference sequence) from Genbank (NC_012920) revealed 3929 distinct variants  in 108 individuals with 1663 variants in the Tay ethnic group, 905 variants in the Thai ethnic group and 1361 variants in the Nung ethnic group. Nucleotide diversity (π) and haplotype were highest in the Thai ethnic group, being 0.0023 and 0.989, respectively. The genetic distances between each ethnic group pair (Tay-Nung, Tay-Thai and Thai-Nung), as shown by the FST values, were 0.03101; 0.00447 and 0.03282, respectively. Haplogroup analysis showed that 108 studied individuals belonged to 33 different haplogroups, belonging to 2 groups of haplogroups M and N. The most frequent haplogroups in Tay Thai and Nung were B4, F1 and M7, respectively. The results of this study show that although belonging to the same Tai - Kadai language family, the mitochondrial genomes among the three ethnic groups Tay, Thai, and Nung still have notable differences.