The Genetic Relationship of Vietnamese Pigs in Central Highlands Assessed by Cytochrome b

Le Thanh Long,Nguyen Thi Phuong Mai,Doan Chinh Chung,Do Minh Si,Ho Nguyen Quynh Chi,Hoang Nghia Son

doi:10.4236/ojgen.2014.45033

Abstract

To estimate the genetic relationship of Vietnamese pigs in Central Highlands, we compared cytochrome b sequences of Vietnamese wild boars and Vietnamese domestic pigs with other Asian and European wild boars. The results showed that there were two wild boar populations locating in Vietnam Central Highlands including wild boars of group I and wild boars of group II. The Vietnamese wild boars of group II and domestic pigs were genetically close to Asian A1 and Asian A2 wild boar groups, whereas the Vietnamese wild boars of group I were genetically distinct from Asian A1, Asian A2 wild boar groups. The phylogenetic tree demonstrated that the Vietnamese wild boars of group I were clustered in one clade which was distinct from Asian wild boars and Europe wild boars. In addition, the Vietnamese wild boars of group I were estimated to have diverged from European wild boars at 421500 YBP, indicating that Vietnamese wild boar of group I could be isolated from other Asian wild boars. The single nucleotide polymorphism analysis showed that three Asian haplotypes were contributed in Vietnamese wild boars including A3 (TATG) haplotype in Vietnamese wild boar of group I and A1 (CATA) haplotype and A2 (CATG) haplotype in Vietnamese wild boars of group II. The A1 haplotype and A2 haplotype were also distributed in Vietnamese domestic pigs. Thus, there is a high possibility that Vietnam Central Highlands is a principal source for research on genetic diversity in Asian wild boar and domestic pig populations.

Highlights

Mitochondrial DNA has been used to perform phylogenetic studies in animal species
The genetic distance between groups was calculated based on the maximum-likelihood method showed that all haplotypes of Vietnamese wild boars of group I, all haplotypes of Vietnamese wild boars of group II (0.0008 ± 0.0004 within group), and all haplotypes Vietnamese domestic pigs (0.0042 ± 0.0011) formed three distinct clusters that are well separated from each other (Table 3)
Single nucleotide polymorphism of cytochrome b gene was applied to analyze the genetic relationship within these Vietnamese domestic pigs and wild boars and other wild boars

Summary

Introduction

Mitochondrial DNA has been used to perform phylogenetic studies in animal species. One of the regions of mtDNA used when establishing phylogenetic relationships among various species, and in species identification, is a fragment of the gene coding cytochrome b [1]. Mitochondrial DNA data revealed multiple centers of domestication across Eurasia [3] and phylogenetic analysis of porcine mtDNA demonstrated that Asian groups and European groups diverged well with divergence time 900000 YBP [4] [5]. Another study showed that the D-loop sequences of Vietnamese indigenous domestic pigs in the Northern of Vietnam were extremely diverse and were thought to have contributed to the diversity of mtDNA among East Asian domestic pigs [8]. The genetic relationship of Vietnamese domestic pig and wild boar populations have been poorly characterized in other areas of Vietnam; especially, the distribution of Asian haplotype or European haplotype in Vietnamese pigs was still unknown. We aimed to compare sequences of Vietnamese pigs from the Vietnam Central Highlands with Asian and European wild boars and assess the genetic relationship based on cytochrome b. The Asian and European haplotypes distribution in Vietnamese wild boars and domestic pigs was estimated

Objectives

Results

Conclusion