A comprehensive global perspective on phylogenomics and evolutionary dynamics of Small ruminant morbillivirus
Muhammad Zubair Shabbir, Aziz Ul‐Rahman, Muhammad Munir
Abstract
Abstract A string of complete genome sequences of Small ruminant morbillivirus (SRMV) have been reported from different parts of the globe including Asia, Africa and the Middle East. Despite individual genome sequence-based analysis, there is a paucity of comparative genomic and evolutionary analysis to provide overarching and comprehensive evolutionary insights. Therefore, we first enriched the existing database of complete genome sequences of SRMVs with Pakistan-originated strains and then explored overall nucleotide diversity, genomic and residue characteristics, and deduced an evolutionary relationship among strains representing a diverse geographical region worldwide. The average number of pairwise nucleotide differences among the whole genomes was found to be 788.690 with a diversity in nucleotide sequences (0.04889 ± S.D. 0.00468) and haplotype variance (0.00001). The RNA-dependent-RNA polymerase ( L ) gene revealed phylogenetic relationship among SRMVs in a pattern similar to those of complete genome and the nucleoprotein ( N ) gene. Therefore, we propose another useful molecular marker that may be employed for future epidemiological investigations. Based on evolutionary analysis, the mean evolution rate for the complete genome, N , P , M , F , H and L genes of SRMV was estimated to be 9.953 × 10 –4 , 1.1 × 10 –3 , 1.23 × 10 –3 , 2.56 × 10 –3 , 2.01 × 10 –3 , 1.47 × 10 –3 and 9.75 × 10 –4 substitutions per site per year, respectively. A recombinant event was observed in a Pakistan-originated strain (KY967608) revealing Indian strains as major (98.1%, KR140086) and minor parents (99.8%, KT860064). Taken together, outcomes of the study augment our knowledge and current understanding towards ongoing phylogenomic and evolutionary dynamics for better comprehensions of SRMVs and effective disease control interventions.