快大型黄羽肉鸡肉品质性状的遗传参数估计和关键基因挖掘

Genetic Parameters Estimation and Key Genes Identification for Meat Quality Traits of Fast-growing Yellow-feather Meat-type Chickens

旨在挖掘快大型黄羽肉鸡胸肌肉品质性状的重要候选区间和基因。本研究以1923只快大型黄羽肉鸡为素材,于56日龄屠宰并测定屠宰和胸肌肉品质性状;利用“京芯一号”55K SNP芯片进行基因分型,利用传统最佳线性无偏预测(BLUP)、基因组最佳线性无偏预测(GBLUP)和全基因组关联分析(GWAS)等方法进行遗传参数估计和QTL区间/关键基因的检测。结果显示,胸肌pH、肉色L*值和b*值的遗传力中等(0.21~0.38),肉色a*值的遗传力较低(<0.20)。GWAS共鉴定到18个达到全基因组水平潜在显著阈值的SNPs和5个达到全基因组显著水平阈值的SNPs,分别位于3、5(Chr5:48.49~49.06 Mb)、11(Chr11:15.51~15.69 Mb)和28号染色体上,这些SNPs能解释肉品质性状1.51%~8.19%的遗传变异。鉴定到胸肌pH和肉色性状的候选基因ARHGEF18、BCO1、BEGAIN、CDYL2、DLK1、EVL、NSL1、SLC25A47、WARS、ZFYVE26。其中,BCO1是已报道的鸡胸肌肉色b*值的主效基因;SLC25A47属于溶质载体家族成员,影响L*24 h。同时发现,位于5号染色体上的2个单倍型对胸肌pH、肉色性状均有极显著影响。以上结果为黄羽肉鸡肉品质遗传选择方案优化和分子育种技术研发奠定了重要基础。

This experiment aimed to excavate the effective regions and key genes related to meat quality traits in fast-growing yellow-feather meat-type chickens.In this experiment,1923 fast-growing yellow-feather meat-type chickens were slaughtered at 56 days of age to measure carcass and meat quality traits,and genotyped with the customized chicken 55K SNP array.The genetic parameters for carcass and meat quality traits were estimated using the traditional best linear unbiased prediction(BLUP)and genomic best linear unbiased prediction(GBLUP)methods.The key QTL regions and genes were detected using genome-wide association study(GWAS).The results showed that the estimated heritability of pH,meat color L*and b*was moderate(0.21-0.38),and the estimated heritability of meat color a*was low(<0.20).Five genome-wide significant SNPs and 18 suggestively significant SNPs were detected.These SNPs were located on the chromosome 3,5(Chr5:48.49-49.06 Mb),11(Chr11:15.51-15.69 Mb),and 28,and could account for 1.51%-8.19%of the genetic variance of meat quality traits.The identified candidate genes for pH and meat color traits included ARHGEF18,BCO1,BEGAIN,CDYL2,DLK1,EVL,NSL1,SLC25A47,WARS,and ZFYVE26.Among them,BCO1 was the major gene affecting meat color b*value reported in chickens.SLC25A47 affected L*24 h as a member of the solute vector family.In addition,the results showed that two haplotypes on chromosome 5 had extremely significant effects on pH and meat color traits.These results lay an important foundation for the optimization of genetic selection scheme and the development of molecular breeding technology for meat quality of yellow-feather meat-type chickens.