A 6-bp deletion in the TYRP1 gene causes the brown colouration phenotype in Chinese indigenous pigs.
Brown coat colour has been described in Chinese-Tibetan, Kele, and Dahe pigs. Here, we report the identification of a causal mutation underlying the brown colouration. We performed a genome-wide association study (GWAS) on Tibetan and Kele pigs, and found that brown colours in Chinese breeds are controlled by a single locus on pig chromosome 1. By using a haplotype-sharing analysis, we refined the critical region to a 1.5-Mb interval that encompasses only one pigmentation gene: tyrosinase-related protein 1 (TYRP1). Mutation screens of sequence variants in the coding region of TYRP1 revealed a strong candidate causative mutation (c.1484_1489del). The protein-altering deletion showed complete association with the brown colouration across Chinese-Tibetan, Kele, and Dahe breeds by occurring exclusively in brown pigs (n=121) and lacking in all non-brown-coated pigs (n=745) from 27 different breeds. The findings provide the compelling evidence that brown colours in Chinese indigenous pigs are caused by the same ancestral mutation in TYRP1. To our knowledge, this study gives the first description of GWAS identifying causal mutation for a monogenic trait in the domestic pig.
Key Laboratory for Animal Biotechnology of Jiangxi Province and the Ministry of Agriculture of China, Jiangxi Agricultural University, Meiling Road, Nanchang, PR China.
J
J
Ren
H
H
Mao
Z
Z
Zhang
S
S
Xiao
N
N
Ding
L
L
Huang
D000818:Animals; D001483:Base Sequence; D002681:China; D004252:DNA Mutational Analysis; D017931:DNA Primers / Q000235:genetics; D055106:Genome-Wide Association Study; D006197:Hair / Q000502:physiology*; D008969:Molecular Sequence Data; D010088:Oxidoreductases / Q000235:genetics*; D010858:Pigmentation / Q000235:genetics* / Q000502:physiology; D017384:Sequence Deletion / Q000235:genetics*; D013552:Swine / Q000235:genetics* / Q000502:physiology
D017931:DNA Primers; D010088:Oxidoreductases; C064056:tyrosinase-related protein-1