甘肃马鹿MyoG基因5′UTR单核苷酸多态性检测及其序列变异分析

Detection of Single Nucleotide Polymorphisms and DNA Sequence Variation Analysis on 5′UTR of MyoG Gene in Gansu Wapiti(Cervus Elaphus Kansuensis)

为了初步探索肌细胞生成素(MyoG)基因在鹿科动物上的遗传多态性,试验采集56头甘肃马鹿的血液样品,采用PCR-SSCP和克隆测序的方法对MyoG基因(GenBank登录号:FJ746497)5′UTR部分序列进行了单核苷酸多态性(SNPs)检测及序列变异分析。结果表明:①引物P1的PCR扩增片段存在多态性,经克隆测序分析,在5′UTR-237 bp处存在G→A的转换变异,该位点表现为AA、AB和BB 3种基因型,由A和B 2个等位基因控制;对基因型、等位基因频率及群体遗传多态性分析结果发现,AA基因型频率最高,A基因为优势等位基因,该位点多态信息含量(PIC=0.194)为低度多态(PIC<0.25);经TFSEARCH 1.3分析软件预测发现,该变异可能减少了1个Sp1转录因子。②引物2的PCR扩增片段检测到1个SNP多态位点(—46 bp,G→A),表现为CC、CD和DD 3种基因型,基因型频率分布为CC>CD>DD,该位点多态信息含量(PIC=0.266)为中度多态(0.25<PIC<0.5),但该变异并未引起潜在调控元件及蛋白质结合位点的改变。本研究结果为进一步分析MyoG基因SNPs位点与甘肃马鹿胴体、肉质性状的关联性奠定了基础。

The aim of the present study was to explore the genetic polymorphisms of myogenin（MyoG）gene in Cervidae.With the blood of 56 Gansu wapiti as experimental materials,PCR-SSCP and DNA sequencing approaches were applied to detect the single nucleotide polymorphisms（SNPs） and analyze the sequence variation at partial 5′UTR of MyoG gene.The results indicated that： ① The products amplified by primer 1 displayed polymorphism,three genotypes（AA,AB and BB） were detected in Gansu wapiti.The sequencing results showed that there was one single nucleotide mutation（G-237→A-237） at 5′UTR of MyoG gene.The polymorphism site was controlled by two alleles of A and B.Analysis of population genetics suggested that the genotype frequency of AA was the highest and A was the dominant allele gene.They were in low polymorphism（PIC=0.194） in PIC mutation site in 56 Gansu wapiti.There would be one Sp1 transcription factor missing at the mutation site by applying an analysis tool of TFSEARCH 1.3.② Three genotypes（CC,CD and DD） determined by a SNP at —46 bp（G→A） were identified using primer 2,the genotype frequencies were in the order of CC〉CD〉DD,the PIC value（0.266） was intermediate polymorpgism（0.25〈PIC〈0.50）.However,the potential elements and protein factors were not changed.This work would lay the foundation for further study on relationship between SNPs and carcass and meat quality traits in Gansu wapiti.