Assessing the genetic diversity of South-western Nigerian Indigenous Pig (Sus scorfa) using mitochondrial DNA D-loop sequence

Abstract

In this study, the maternal genetic diversity and phylogenetic relationship of South-western pig population were assessed. Deoxyribonucleic acid (DNA) was extracted from air-dried blood spotted on Fast Technology for Analysis (FTA) card. The extracted DNA were amplified with predefined mitochondria (mtDNA) primers. A total of 843 base pair fragment of the mitochondrial DNA (mtDNA) D-loop region of 30 pigs were analyzed. Seven (7) haplotypes and 64 polymorphic sites were identified, with no insertion or deletion between nucleotide 3 and 835. The mean haplotypic and nucleotide diversity were found to be 0.381±0.058 and 0.315±0.155 respectively. The phylogeny revealed one divergent haplotype clade, suggesting one possible maternal lineage (European domestic pig) in South-west Nigerian pigs. The median joining network formed a star-like pattern, suggesting population expansion from a small number of founding ancestor (IFE1). Genetic variation within and between populations accounted for 63.32% and 36.68% of the total genetic variation respectively. This study concluded that there was relatively high genetic diversity in our indigenous pig population, thus, will probably pave way for preservation and improvement of Nigerian pigs as genetic resources.

Keywords: mtDNA, genetic variation, phylogenetic relationship