摘要
采用PCR-SSCP方法,对中国宁夏固原鸡、海南文昌鸡、西藏藏鸡和国外引进海赛克斯鸡TYR基因5′侧翼区及外显子13个位点(P1、P2、P3)的遗传变异进行研究。结果表明,P2位点无多态,P1位点在3个中国鸡品种中均出现3种基因型,分别为AA型、BB型和AB型;在引进的海赛克斯鸡中,只检测到BB型和AB型2种类型。4个鸡品种在该位点均处于Hardy-Weinberg平衡状态;P3位点在中国3个鸡品种中均检测到3种基因型,分别为AA型、BB型和AB型,而海赛克斯鸡中只检测到AA和AB型,固原鸡和文昌鸡在该位点处于Hardy-Weinberg平衡状态,藏鸡和海赛克斯鸡均处于极不平衡状态。进一步说明,中国地方鸡品种的TYR基因蕴藏丰富变异资源。经克隆测序分析,P1位点存在C→T的单碱基替换突变,P3位点存在G→A的单碱基替换突变,但未引起氨基酸突变。独立χ2分析显示,两位点基因型和等位基因分布在不同鸡品种之间存在显著或极显著差异(P<0.05和P<0.01),提示TYR基因的基因型和等位基因分布与鸡品种因素显著相关。本研究为以后对鸡TYR基因5′侧翼区及外显子1的进一步研究提供基础依据。
In order to study genetic variation of TYR gene in four chicken breeds selected from special district including Guyuan,Wenchang,Tibetan and Hisex chicken,two sites of the gene exon1 and one site of 5′ flanking region were analyzed by PCR-SSCP and DNA sequencing.The result indicated： there was no polymorphism at P2 site,while at P1 site,there were three genotypes（AA,BB,AB） in three Chinese chicken breeds respectively.They were all in equilibrium at P1 site.At P3 site,there were three genotypes（AA,BB and AB） in Chinese local chicken breeds（Guyuan,Wenchang and Tibetan chicken） and two genotypes（AA and AB） in Hisex chicken breed.Guyuan and Wenchang breeds were in equilibrium at the site,but Tibetan and Hisex breeds were extremely in unbalance.It is concluded that there was abundant variation of TYR gene in Chinese local chicken breeds.DNA sequencing of PCR products for different genotypes showed that there were two mutation sites： C to T at P1 site and G to A at P3 site,respectively,which didn＇t cause amino acid variation at P1 site.The chi-square analysis revealed that there was significant statistical difference in distribution of genotype and allele frequencies at the two TYR sites among the analyzed four chicken populations（P〈0.05 and P〈0.01）.It revealed that there was significant association between genotype and chicken breeds.This study provided original information for elucidating the possible roles of TYR gene of exon1 and 5′ flanking region in different chicken populations.
出处
《畜牧兽医学报》
CAS
CSCD
北大核心
2008年第9期1153-1158,共6页
ACTA VETERINARIA ET ZOOTECHNICA SINICA
基金
国家自然科学基金项目(30460097)
西北农林科技大学青年专项项目(08080251)
