Highly diverse TTV population in infants and their mothers

Infants born to serum HCV-positive 12 mothers were enrolled in the study. N ucleotide sequences amplified by primers deduced from a noncoding region we re compared between mothers acid their infants. The rates for detection of serum TTV in 12 mothers and their infants were 10/12 (83%) and 9/12 (75%), respectively. Serum TTV DNA was not detected in any infant at 1 month of ag e, but was detected for the first time between 1.5 and 8 months after birth . Positivity persisted thereafter throughout the follow-up period. In seven randomly selected mother-infant pairs, intrahost TTV heterogeneity was low er in infants than in mothers. Furthermore, one of seven mother-infant pair s showed a high degree of similarity (98.7-100%) in all clones, while in fo ur infants, all nucleotide sequences differed by > 10% from those of their mothers. However, the degree of homology in the two mother-infant pairs was 89-98.7% in family 2 and 88.1-99.4% in family 5. In the present study, wit h only one exception, it was shown that TTV from infants is not identical t o TTV from mothers. The mechanism is discussed briefly in this paper. (C) 2 001 Elsevier Science B.V. All rights reserved.