【摘要】 角化细胞相关蛋白3基因(keratinocyte-associated protein 3, KRTCAP3)主要调节角蛋白表达进而影响机体皮肤、指甲和毛发的生长发育。为了解KRTCAP3基因在’南甘’杂交绵羊(Ovis aries)群体中的遗传变异及其与产毛和生长性状之间的关系,本研究以南非肉用美利奴(Ovis aries)(♂)×甘肃高山细毛羊(♀)(’南甘’)及南非肉用美利奴(♂)×’南甘’(♀)(’南南甘’)杂种羊为研究对象,采用DNA混合池测序结合SNPscanTM高通量SNP分型技术对KRTCAP3的基因全长进行SNP扫描,同时分析SNP位点与杂种羊产毛和生长性状的相关性。结果表明,在KRTCAP3基因第2内含子上发现1个g.34287851C>G的SNP位点,鉴定到CC、CG和GG 3种基因型,其基因型频率分别为0.35、0.52和0.13,C和G等位基因频率分别为0.61和0.39。遗传参数分析发现,杂合度(heterozygosity, He)、纯合度(homozygosity, Ho)、有效等位基因数(effective number of alleles, Ne)和多态信息含量(polymorphic information content, PIC)分别为0.47、0.53、1.90和0.36,属于中度多态(0.25<PIC<0.50)。χ~2适合性检验表明,该SNP在研究群体中不处于HardyWeinberg平衡状态(P<0.05)。SNP与毛用性状的关联分析发现,该SNP位点与肩部和体侧毛长、股部和背部毛长、羊毛卷曲度和卷曲回复率相关(P<0.05或P<0.01);SNP与生长性状的关联分析发现,该位点与管围和胸围性状相关(P<0.05或P<0.01)。综上,KRTCAP3基因g.34287851C>G位点可作为分子标记辅助选育的候选分子标记,在细毛羊品种选育和培育肉毛兼用新品种中利用,加快育种进程。更多还原

【Abstract】 The keratinocyte-associated protein 3 gene(KRTCAP3) affects the growth of skin, nails and hair by regulating keratin. In order to uncover the genetic variation in the KRTCAP3 gene and its genetic roles in wool production and growth performance in nangan(South African Mutton Merino( ♂) × Gansu alpinefinewool(♀)) and nannangan(South African Mutton Merino(♂)×nangan(♀)) crossbred sheep breed. DNA pool sequencing was used to scan the potential SNPs within the full-length DNA of KRTCAP3 gene in AF × MF population. The correlation between SNP locus and hair growth and growth traits of hybrid sheep was also analyzed. Six hundred crossbred sheep were individually genotyped by SNPscanTMmethod. Then, the association analysis between SNP locus and wool production and growth performance was implemented. The results showed that one SNP(g.34287851 C>G) was identified in intron2. Three genotypes, CC, CG and GG,in this locus were found in AF×MF crossbreed sheep population. The genotypic frequencies of CC, CG and GG were 0.35, 0.52 and 0.13, respectively. The allelic frequencies of C and G were 0.61 and 0.39,respectively. The population genetic parameters analyses showed that the homozygosity(Ho), heterozygosity(He) and effective allele number(Ne) were 0.53, 0.47 and 1.90, respectively. The polymorphism information contents(PIC) was 0.36 and suggested that this SNP was moderate diversity(0.25<PIC<0.5). The χ~2 test indicated that this locus was not in Hardy-Weinberg equilibrium(P<0.05). The association analysis of polymorphisms in KRTCAP3 gene with wool traits revealed that g.34287851 C>G was significantly associated with the wool length of shoulder and side, wool length of thigh and notum, crimpness and crimp recovery(P<0.05 or P<0.01). The association analysis of polymorphisms in KRTCAP3 gene with growth performance revealed that g.34287851 C>G was significantly associated with tube circumference and chest girth(P<0.05 or P<0.01). In summary, the g. 34287851 C>G site in KRTCAP3 gene could be used as a useful molecular marker for selection wool traits and growth performance. This study provides a molecular basis for utilization of fine wool resources and accelerates the breeding progress.更多还原