北京地区荷斯坦牛脊椎畸形综合征的调查研究

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。本研究利用PCR-SSCP方法对北京地区242头公牛样品和403头母牛样品进行了检测分析,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8.82%和5.71%,CVM基因频率分别为4.41%和2.85%。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遗传缺陷的传播,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。

Investigation on Complex Vertebral Malformation (CVM) in Holstein Cattle of Beijing

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 can be increased by use of carrier bulls in Artificial Insemination（AI）.In this study,DNA samples from Holstein bulls（n=242）and cows（n=403）in Beijing district were detected by PCR-SSCP.The results showed that CVM-carrier rates in Holstein bulls and cows were 8.82%and 5.71%, and their gene frequencies were 4.41%and 2.85%,respectively.Our pedigree studies of the carrier cattle in this experiment revealed that the mutation was 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 were 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.