Genetic diversity and evolution of human metapneumovirus fusion protein over twenty years.
BACKGROUND
Human metapneumovirus (HMPV) is an important cause of acute respiratory illness in children. We examined the diversity and molecular evolution of HMPV using 85 full-length F (fusion) gene sequences collected over a 20-year period.


RESULTS
The F gene sequences fell into two major groups, each with two subgroups, which exhibited a mean of 96% identity by predicted amino acid sequences. Amino acid identity within and between subgroups was higher than nucleotide identity, suggesting structural or functional constraints on F protein diversity. There was minimal progressive drift over time, and the genetic lineages were stable over the 20-year period. Several canonical amino acid differences discriminated between major subgroups, and polymorphic variations tended to cluster in discrete regions. The estimated rate of mutation was 7.12 x 10(-4) substitutions/site/year and the estimated time to most recent common HMPV ancestor was 97 years (95% likelihood range 66-194 years). Analysis suggested that HMPV diverged from avian metapneumovirus type C (AMPV-C) 269 years ago (95% likelihood range 106-382 years).


CONCLUSIONS
HMPV F protein remains conserved over decades. HMPV appears to have diverged from AMPV-C fairly recently.
Yang
Chin-Fen
CF
Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, TN, USA. yangc@medimmune.com
Wang
Chiaoyin K
CK
Tollefson
Sharon J
SJ
Piyaratna
Rohith
R
Lintao
Linda D
LD
Chu
Marla
M
Liem
Alexis
A
Mark
Mary
M
Spaete
Richard R
RR
Crowe
James E
JE
Williams
John V
JV
D019143:Evolution, Molecular; D014644:Genetic Variation; D006801:Humans; D029121:Metapneumovirus / Q000737:chemistry / Q000145:classification / Q000235:genetics*; D008969:Molecular Sequence Data; D010802:Phylogeny; D014760:Viral Fusion Proteins / Q000737:chemistry / Q000235:genetics*
D014760:Viral Fusion Proteins