PEG1基因影响动物胚胎生长及母性行为, 多数动物PEG1为父方表达的遗传印记特征, 但出生后猪的PEG1印记表达尚不清楚。因此, 文章选取长白、大白和蓝塘3个品种共166头纯种猪, 在猪的PEG1基因外显子12区域内寻找SNP, 采用PCR-SSCP方法对其多态性进行检测和基因频率分析; 取带有PEG1基因该位点SNP为杂合的仔猪3头, 对其胃、胸腺、胰、脾、肺、肌肉、肝、舌、肾、脑、膀胱、心脏等组织器官和胎盘的mRNA产物分别进行RT-PCR-SSCP分析, 结果表明: PEG1基因外显子12存在一个由G突变为A的单核苷酸多态性位点; PEG1的外显子12在3头仔猪的主要组织器官仅表达父亲来源的等位基因, 表明猪的PEG1基因呈母方印记、父方表达的遗传特征。
PEG1 affects animal embryo growth and maternal behavior. The paternal allele-specific expression of PEG1 was reported in most animal species, but the expressive pattern of PEG1 was not clear in piglets born. In order to investigate the imprinting pattern of PEG1 in pig, 166 samples were used to SNP of PEG1 from Landrace, Yorkshire, and Lantang breeds by PCR-SSCP. Single nucleotide polymorphism (SNP) of PEG1 in exon 12 was identfied. The genotype frequency and the expressive pattern were anslyzed in swine by RT-PCR-RFLP/SSCP. One SNP (a G→A transition) was identified in exon 12 of PEG1. Maternal expression of PEG1 exon 12 was observed in all major organs (stomach, thymus, pancreas, spleen, lung, muscle, liver, tongue, kidney, brain, bladder, and heart) and placenta of three heterozygous pigs. PEG1 was paternally expressed and maternally imprinted in swine.
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