荷斯坦牛脊椎畸形综合征分子诊断方法的建立与应用

Establishment and Application of Molecular Diagnosis of Complex Vertebral Malformation (CVM)in Holstein

脊椎畸形综合征(Complex Vertebral Malformation,CVM)是由常染色体上SLC35A3基因单碱基突变(G→T)引起的隐性遗传疾病,该基因隐性纯合(CV/CV)时奶牛致死,但CVM携带者表现正常,所以CVM携带者公牛可以通过人工授精技术传播CVM缺陷基因。本研究自行设计检测CVM特异性PCR引物,扩增长度为173bp,然后利用PCR-SSCP方法对186个公牛样品和140个母牛样品进行了检测分析,该方法简便快捷、准确率高,使用样品宽泛,适合大样本筛选。研究结果表明,在所检测的样本中,荷斯坦种公牛和母牛CVM携带率分别为11.3%和12.1%,并通过系谱追踪发现,CVM遗传缺陷的共同祖先是美国名牛"Penstate Ivanhoe Star"(USA.1441440,CV)。通过剔除CVM携带者公牛可以有效地控制CVM遗传缺陷,但是,我国许多CVM携带者公牛冻精依然在商业化使用,所以,有效地监控CVM携带者在奶牛群中的状况对CVM防控计划是有益的。

Complex Vertebral Malformation（CVM） is an autosomal recessive disease caused by G→T mutation in the SLC35A3 gene. The recessive homozygous form（CV/CV）is lethal and since carrier animals have viability, CVM frequency increases by use of carrier bulls in Artificial Insemination（AI）. In this study DNA samples from Holstein bulls（n=186） and cows（n=140）were analysed. A 173 bp fragment from the polymorphic region of SLC35A3 gene was amplified by PCR and CVM was detected by PCR-SSCP in a simple, highly accurate and high throughput manner. Frequencies of CV/TV（earrier） genotypes in Holstein bulls and cows were 11.3% and 12.1%, respectively. Our pedigree studies of the carrier cattle in this experiment revealed that the mutation inherited to him from Penstate Ivanhoe Star bull（USA. 1441440, CV）. Although the elimination of CVM-carrier bulls from the Holstein world would be the most efficient method to control this genetic disorder, many CVM-carrier bulls are still listed commercially for. AI in China. Monitoring the prevalence of CVM-carriers in random selected herds may be helpful in judging the effectiveness of the CVM-control program.