The linkage disequilibrium (LD) plot showing non-random association between nucleotide variants at different polymorphic sites. The R^2 values are plotted against the nucleotide distances with two-tailed Fisher's exact test of significance using DnaSP. The value of LD index (range from -1 to +1) declines with increasing nucleotide distance, indicating that recombination events are taking place. The analysis was performed considering all polymorphic sites. (A) Assam, (B) Orissa, (C) A & N, (D) Goa, (E) UP, and (F) Total.