TRIM5α is a retroviral restriction factor, in which the B30.2 (SPRY) and 
coiled-coil domains cooperate to determine the specificity of TRIM5α-mediated 
capture of retroviral capsids. Here, all exons of TRIM5α were analyzed in 39 
Vietnamese cynomolgus macaques (VCE) and 29 Chinese rhesus macaques (CR). Our 
results revealed the presence of 22 alleles using the PHASE 2.0 software package 
(PHylogenetics And Sequence Evolution), including two novel species-specific 
alleles with a low frequency in VCE in exons 4 and 8, which encoded the 
coiled-coil and B30.2 (SPRY) domains, respectively. Nine alleles were detected 
in both VCE and CR, while four alleles were likely shared between the species. 
Of these alleles, the highest frequencies of 38% and 26% occurred in VCE and CR, 
respectively. Importantly, we found that some alleles encoded the same 
coiled-coil domain, but not the SPRY domain. In contrast, other alleles encoded 
the same SPRY domain, but not the coiled-coil domain. Our findings will 
contribute to the understanding of the interaction between the two domains and 
the determination of the specificity of TRIM5α-mediated capture of retroviral 
capsids. Our results from the phylogenetic trees constructed for VCE and CR 
suggested that the macaques' ability to inhibit SIV replication became gradually 
stronger if they carried corresponding alleles in four clades (clades4-7). More 
interesting, in clade3, both novel allele pairs (4E100a, 10E147a) and allele 
pairs (7R17b and 13R11b), which had the strong ability to inhibit SIV 
replication, originated from the same ancestral allele, suggesting that the 
novel alleles might play a key role to determine an animal's ability to inhibit 
SIV/HIV replication. However, further studies are needed to increase our 
understanding of the genetic background of TRIM5α in these two macaque species.