猪SDHD和DCN基因多态性及遗传印记

Study on SNPs and Genomic Imprinting of the SDHD and DCN Gene in Swine

为揭示猪SDHD和DCN基因印记表达特征,该研究以长白、大白、蓝塘3个品种的166头纯种猪为试验材料,在猪的SDHD和DCN基因的外显子内寻找SNP,通过PCR-SSCP方法对SDHD和DCN基因多态性进行检测;分别选取SDHD基因外显子4和DCN基因外显子2的SNP为杂合子的仔猪3头,以其主要的组织器官mRNA的产物分别进行RT-PCR-RFLP电泳和RT-PCR-SSCP电泳.结果表明:SDHD基因外显子4中有1个单核苷酸多态性位点,即131位碱基由G突变为T,且该位点为MboI酶切位点;DCN基因外显子2中有1个单核苷酸多态性位点,即编码区30位碱基由T突变为A;SDHD基因外显子4和DCN基因外显子2在上述3头仔猪的胃、胸腺、胰、脾、肺、肌肉、肝、舌、肾、脑、膀胱、心脏等主要组织器官和胎盘同时表达父母双方来源的等位基因.可见,SDHD和DCN基因在猪呈父母双方表达的遗传特征.

In order to investigate the imprinting pattern of SDHD and DCN,one hundred and sixty-six samples were used to scan the SNPs of SDHD and DCN from Landrace,Yorkshire and Lantang breeds by PCR-SSCP;Expression of SDHD exon 4 and DCN exon 2 were observed in organs and placenta of three heterozygous piglets by RT-PCR-RFLP/SSCP.One SNP（a G→T transition） was identified in exon 4 of SDHD,located at the 131st nucleotide（5→3）,which was a MboI restriction site.One SNP（a T→A transition） was identified in exon 2 of DCN,located at the 30th nucleotide.Biallelic expression of exon 4 of SDHD and exon 2 of DCN were showed in the main organs（stomach,thymus,pancreas,spleen,lung,muscle,liver,tongue,kidney,brain,bladder,heart） and placenta of three heterozygous pigs.In conclusion,SDHD and DCN were biallelically expressed in swine.