V3 SEQUENCE DIVERSITY OF HIV-1 SUBTYPE-E IN INFECTED MOTHERS AND THEIR INFANTS

To elucidate genetic characteristics of HIV-1 subtype E involved in ve rtical transmission, V3 regions of HIV-1 subtype E isolated from 17 in fected mothers (M1-M17) and their infants (I1-I17) at 1 month after bi rth were sequenced after cloned into pCRII vectors. At least three clo nes of each sample were collected. All mothers were asymptomatic and h ad been infected through a heterosexual route. Nine infants (I9-I17) s howed mild symptomatic and immunosuppression within the first year of life. The interpatient nucleotide distance of mothers and infants in t his group (0.065 +/- 0.008) were of greater diversity than those of a nonimmunosuppression group (0.039 +/- 0.006) by a significant amount ( Fischer's exact test, p =.003). The substitution with asparagine (N) a t threonine (T) at position 13 and aspartic acid (D) at position 29 of the V3 sequence were significantly associated with nonimmunosuppressi on in the first year of life (F-test, p = 0.003). Either a single or m ultiple viral variants could transmit from mothers to their infants.