Plant & Animal Genomes XIII Conference

January 15-19, 2005
Town & Country Convention Center
San Diego, CA

Mapping Of The Locus Causing Tibial hemimelia (TH) In Shorthorn Cattle

Brandy M. Marron¹ , Geri Thurnau¹ , Charles P. Hannon² , Jonathan E. Beever¹

¹  University of Illinois at Urbana-Champaign, Department of Animal Sciences, Urbana, IL, 61801, USA

²  Food Animal Veterinary Serice P.C., Rensselaer, IN, 47978, USA

Tibial hemimelia is a congenital abnormality present in Shorthorn cattle that is characterized by severe and lethal deformities in newborn calves. These deformities can range from bilateral shortening or malformation of the tibia with joint fusion to completely absent tibia. Other defects include abdominal hernia due to incomplete fusion of the pelvic symphysis and meningoceles. Pedigree analysis suggests a putative autosomal recessive mode of inheritance with a single proband sire. DNA samples from 20 affected calves along with their sires and most dams have been collected as well as samples from putative homozygous normal individuals that are not related to the proband. A total of 265 microsatellite markers distributed evenly across the bovine autosomes have been selected for genotyping and homozygosity analyses. Analysis of genotypic data for eight chromosomes having candidate genes corresponding to human and mouse disease loci with similar phenotypes has not revealed any significant results. However, a multi-generation family is currently being constructed through collection of additional samples and a traditional linkage analysis will be performed. Results of this study will aid in the discovery of the causative mutation of th and the development of a DNA-based diagnostic test.