To figure out the relationship between the nucleotide sequence of MC1R gene and the formation of melanin, the physicochemical property and molecular structure of Lueyang Silky Fowl were detected by PCR-SSCP and sequencing. The results showed that the variations of MC1R were very small in Lueyang chicken population, but there were seven single nucleotide mutations sites at the 69, 212, 274, 376, 636, 637 and 644 locus of the coding region comparing with White Leghorn breed. Except 69 and 636 locus, the five mutational sites were resulted amino acid sequences changing, and leaded to adding a phosphorylation site in melanocortin receptor 1. All these mutations sites may be correlated with the production and precipitation of melanin in Lueyang Silky Fowl. Cluster analysis indicated that Lueyang Silky Fowl had close genetic relationship with jungle fowl, and had distance genetic relationship with leghorn. Lueyang Silky Fowl was a relatively old breed, and reserved original gene pool; MC1R gene was a major gene resistance regulating melanin trait in Lueyang Silky Fowl.%为弄清略阳乌鸡黑素皮质素受体1(MC1R)基因的遗传变异与黑色素形成的关系,采用PCR-SSCP测序方法,对略阳乌鸡蛋白质理化性质和分子结构进行了研究.结果表明:略阳鸡种内MC1R变异较小,与白来航比对,在编码区69、212、274、376、636、637和644位点有7个SNPs,除69和636位点外,其余 5个突变导致略阳乌鸡的MC1R编码区氨基酸序列发生改变,并造成黑素皮质素受体1多了一个磷酸化位点,这些位点的变异可能与略阳乌鸡黑色素的形成和沉积有关；经聚类分析,略阳鸡与原鸡亲缘关系较近,与来航鸡关系较远.略阳乌鸡保留了原始的基因库,MC1R基因可能是控制略阳乌鸡黑色素形成的主效基因.
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