Drögemüller Cord, Leeb Tosso, Harlizius Barbara, Tammen Imke, Distl Ottmar, Höltershinken Martin, Gentile Arcangelo, Duchesne Amandine, Eggen André
Institute of Genetics, Vetsuisse Faculty, University of Berne, Bremgartenstrasse 109a, 3001 Berne, Switzerland.
BMC Genet. 2007 Feb 23;8:5. doi: 10.1186/1471-2156-8-5.
Isolated syndactyly in cattle, also known as mulefoot, is inherited as an autosomal recessive trait with variable penetrance in different cattle breeds. Recently, two independent mutations in the bovine LRP4 gene have been reported as the primary cause of syndactyly in the Holstein and Angus cattle breeds.
We confirmed the previously described LRP4 exon 33 two nucleotide substitution in most of the affected Holstein calves and revealed additional evidence for allelic heterogeneity by the identification of four new LRP4 non-synonymous point mutations co-segregating in Holstein, German Simmental and Simmental-Charolais families.
We confirmed a significant role of LRP4 mutations in the pathogenesis of congenital syndactyly in cattle. The newly detected missense mutations in the LRP4 gene represent independent mutations affecting different conserved protein domains. However, the four newly described LRP4 mutations do still not explain all analyzed cases of syndactyly.
牛的并指畸形，也称为骡蹄，作为一种常染色体隐性性状遗传，在不同牛品种中的外显率有所不同。最近，已报道牛LRP4基因中的两个独立突变是荷斯坦和安格斯牛品种并指畸形的主要原因。
我们在大多数受影响的荷斯坦犊牛中证实了先前描述的LRP4基因第33外显子的两个核苷酸替换，并通过鉴定在荷斯坦、德国西门塔尔和西门塔尔-夏洛莱家族中共分离的四个新的LRP4非同义点突变，揭示了等位基因异质性的更多证据。
我们证实了LRP4突变在牛先天性并指畸形发病机制中的重要作用。LRP4基因中新检测到的错义突变代表影响不同保守蛋白结构域的独立突变。然而，新描述的四个LRP4突变仍不能解释所有分析的并指畸形病例。
