Estimating the frequency of Asian cytochrome B haplotypes in standard European and local Spanish pig breeds

Abstract

-Mitochondrial DNA has been widely used to perform phylogenetic studies in different animal species. In pigs, genetic variability at the cytochrome B gene and the D-loop region has been used as a tool to dissect the genetic relationships between different breeds and populations. In this work, we analysed four SNP at the cytochrome B gene to infer the Asian (A1 and A2 haplotypes) or European (E1 and E2 haplotypes) origins of several European standard and local pig breeds. We found a mixture of Asian and European haplotypes in the Canarian Black pig (E1, A1 and A2), German Piétrain (E1, A1 and A2), Belgian Piétrain (E1, A1), Large White (E1 and A1) and Landrace (E1 and A1) breeds. In contrast, the Iberian (Guadyerbas, Ervideira, Caldeira, Campanario, Puebla and Torbiscal strains) and the Majorcan Black pig breeds only displayed the E1 haplotype. Our results show that the introgression of Chinese pig breeds affected most of the major European standard breeds, which harbour Asian haplotypes at diverse frequencies (15−56%). In contrast, isolated local Spanish breeds, such as the Iberian and Majorcan Black pig, only display European cytochrome B haplotypes, a feature * Corresponding author: Armand.Sanchez@uab.es 98 A. Clop et al. that evidences that they were not crossed with other Chinese or European commercial populations. These findings illustrate how geographical confinement spared several local Spanish breeds from the extensive introgression event that took place during the 18th and 19th centuries in Europe. mitochondria / cytochrome B / pig breeds / Asian and European haplotypes / introgression

miRNA Expression Profile Analysis in Kidney of Different Porcine Breeds

“…Other studies confirmed some introgression events of Asian pig breeds in most European commercial breeds and evidence that local Spanish breeds have never been introgressed with Asian neither with European commercial populations [47]–[49]. In this sense, studying miRNAs differentially expressed between European and Asian pig breeds could contribute to understand their phenotypical differences.…”

Phylogenetic relationships of pig breeds from Shandong province of China and their influence by modern commercial breeds by analysis of mitochondrial DNA sequences

“…Comparison of Cytb and CR as phylogenetic markers to investigate genetic relationships of pig breeds Both the mtDNA Cytb and CR DNA sequences are widely used as phylogenetic markers in molecular systematics (Ghivizzani et al, 1993;Alves et al, 2003;Clop et al, 2004;Fang and Andersson, 2006;Wu et al, 2007;Jiang et al, 2008). However, compared with Cytb, CR has a larger sequence variation, and is useful to compare the genetic diversity in the study.…”

“…According to their polymorphisms all pigs were classified into the Asian (A1 = CATA and A2 = CATG) or European (E1 = TGCG and E2 = TGTG) origins (Giuffra et al, 2000;Clop et al, 2004) in maternal lineage. In the European domestic pig breeds, not only European but Asian origin haplotypes as well exist, because of the gene introgression from Asian breeds into European population as mentioned above; whereas in Asian domestic pig breeds only Asian origin haplotypes existed.…”

Traditional pig herding practices in southwest Iberia: Questions of scale and zooarchaeological implications

“…It is also one of the few European pig breeds that has remained genetically unaffected by the introgression of Chinese domestic breeds, which have altered to a varying degree (15-56%) the genetic -and consequently phenotypic, behavioural and reproductivecharacteristics of the most commonly exploited breeds of Europe (Alves et al, 2003;Clop et al, 2004). European pig breeds are often divided into two main types, the Celtic, with a general central and northern European origin assumed, and the Iberian or Mediterranean (e.g., Porter, 1993, pp.…”