Melanocyte-stimulating Hormone Receptor (MC1R) Genotype and Its Effects on Coat Color in Korean Jindo Dogs

Kyung-Won Hong,Seung-Min Yang,Dong-Hee Chung,Bong-Hwan Choi,Jong-Seok Kim,Boh-Suk Yang,Yoon-Hye Hong,Hong-Chul Jang,Yun‐Shik Choi ,Sang–Wook Kim ,Seok-Il Oh,Jiwoong Lee ,Young-Bin Shin

doi:10.5713/ajas.2009.80599

Abstract

The Jindo dog is a Korean natural monument and is recognized by the Federation Cynologique Internationale. A prominent feature is the diverse coat color within the breed. To analyze the genetic basis of variation in the Jindo coat color, we sequenced the protein-coding regions of the melanocortin I receptor gene (MC1R). The MC1R coding sequence was determined from 154 dogs in five breeds (Jindo, Labrador Retriever, English Springer Spaniel, Belgian Malinois, and German Shepherd). To confirm the genetic structure of sampled populations, we tested for Hardy-Weinberg equilibrium (HWE) and computed F st . The sample populations did not significantly deviate from HWE. F st was 0.02 between white and fawn Jindo dogs; this was lower than F st between breeds. Six single nucleotide polymorphisms (SNPs) were detected in the MC1R coding region. Among the six SNPs, five were non-synonymous (S90G, T105A, Q159P, M264V, and R306ter) and one was synonymous SNP (Y298Y). From the SNPs, we predicted four haplotypes (H1, H2, H3, and H4) for Jindo MC1R. Jindo dogs had different haplotypes corresponding to different coat colors. H1 was frequently observed in white Jindo dogs with an odds ratio of 5.03 (95% CI: 2.27-11.18, p<0.0001), whereas H2 and H4 were observed only in fawn Jindo dogs. Our findings indicate that SNP haplotype can influence coat color. Knowledge of MCIR haplotypes can help discriminate white and fawn coats in Jindo dogs. We hope this report will trigger more research into the genetics of this traditional Korean dog and will be a reference for dogs of Asian origin. Also, our results will provide a useful genetic marker for Jindo dog breeders who have selected for specific colors.

Highlights

Jindo, a county in South Korea (Figure 1a), consists of islands covering 430.6 km2 and is home to 41,184 people
The S allele was more frequently observed in white JD, Labrador Retriever (LR), BM, and German Shepherd (GSD), but the G allele was more frequently observed in fawn JD and English Springer Spaniel (ESS)
melanocortin 1 receptor gene (MC1R) is a seventransmembrane G-protein coupled receptor (GPCR), and S90G is located in the second transmembrane domain

Summary

INTRODUCTION

A county in South Korea (Figure 1a), consists of islands covering 430.6 km and is home to 41,184 people. Diverse coat colors have been reported in Jindo dogs, including fawn, white, black, red, and brindle (Mori, 1940; Lee and Kim, 1993). We investigated the genetic basis of coat-color variation in Korean Jindo dogs. Korean Jindo dogs with fawn the reverse primer (JdMR), 5’-ATC CAC CAC ACC ACA (b) and white (c) coats. Of DNA, 0.6 μM of each primer, 1 U of Top-TaqTM DNA The EM and e alleles are caused by single nucleotide Polymerase, 10×buffer (CoreBioSystem), and 400 μM polymorphisms (SNPs) in individuals with a melanistic dNTPs. After an initial incubation at 94°C for 5 min, PCR mask and pheomelanic coat color, respectively (Newton et was performed for 35 cycles consisting of 94°C for 30 s, al., 2000; Schmutz et al, 2002, 2003). By 2% agarose gel electrophoresis and were purified with 96-well PCR Cleanup Filter Plates, MultiScreen HTSTM

MATERIALS AND METHODS

RESULTS

H RR K LT 317

Findings

DISCUSSION