Hq. Zheng et al., Genetic variability in envelope-associated protein genes of closely related group A strains of respiratory syncytial virus, VIRUS RES, 59(1), 1999, pp. 89-99
The genetic and antigenic diversity present in respiratory syncytial virus
(RSV) strains may in part be explained by genetic drift similar to that whi
ch occurs with influenza virus B. To study drift in RSV strains, we sequenc
ed the five membrane-associated genes, M, SH, G, F, and M2, from three sets
of RSV isolates: one set of seven closely related isolates obtained over 5
years in St. Louis, MO, and two sets of four closely related RSV isolates
from other communities. We found nucleotide-variable and conserved regions
in all five genes, and the greatest diversity in the SH and G genes. We did
not find clear evidence of genetic drift in the seven isolates from St. Lo
uis for any of the five genes. Although the relationships between strains w
ere usually maintained independent of the genes studied, for several isolat
es there was a dramatic shift in genetic relationships for one of the five
genes. Our inability to demonstrate genetic drift and the dramatic shift in
; genetic relationships between some strains for some genes suggest that we
need to better define the mechanisms and rate of change in this virus to a
ccurately define phylogenetic relationships between strains. (C) 1999 Elsev
ier Science B.V. All rights reserved.