Diversity of HIV type 1 long terminal repeat (LTR) sequences following mother-to-child transmission in North India.

We genetically characterized the extent of variation in HIV-1 LTR sequences from 11 mother-to-child transmission (MTCT) pairs from HIV-1-infected individuals from North India. Nine pairs were found to be infected with subtype C virus whereas two pairs were infected with subtype B virus. They harbored the characteristic three and two NF-κB sites, respectively. The analysis of intrasubtype divergence between B and C revealed greater diversity with subtype B LTR sequences than subtype C (p < 0.005). Significant evolutionary divergence of subtype C and subtype B was found in NFAT-III (p < 0.000001), NFAT-II (p < 0.0001), and USF (p < 0.005) transcription factor binding sites (TFBS). NF-κB-I, Sp I and II, Ets-I, AP-I and II, and TATA Box TFBS were highly conserved in both the subtypes. An alternate secondary structure of Tar was detected in the VT5 sample due to the point mutation from G to C (position +21) and T to C (position +38).