title: Evaluation of quantitative trait loci for hip dysplasia in Labrador Retrievers.
abstract: OBJECTIVE
  To identify the quantitative trait loci (QTL) that contribute to hip dysplasia in dogs.
  
  
  METHODS
  192 Labrador Retrievers.
  
  
  METHODS
  Hip dysplasia was measured by use of the Norberg angle (NA), dorsolateral subluxation (DLS) score, and distraction index (DI). Genome-wide screening was conducted by use of 276 unique microsatellites. Linkage analysis was performed with a variance-based linear model. Logarithm of the odds (LOD) scores were reported when values were > 2.0.
  
  
  RESULTS
  Canis familiaris autosomes (CFAs) 01, 02, 10, 20, 22, and 32 harbored significant QTL at LOD scores > 2.0. Among the 6 QTL, the QTL on CFA02 had not been reported to harbor QTL for hip dysplasia. The highest LOD score of 3.32 on CFA20 contributed to the second principal component of the DLS score and NA of the right hip joint. The QTL that was mapped on CFA01 (LOD score of 3.13 at 55 centimorgans) was located on the same chromosome reported to harbor a QTL for hip dysplasia in Portuguese Water Dogs and German Shepherd Dogs. In this study, CFAs 10, 20, 22, and 32 harbored QTL for hip dysplasia that have been identified in a Labrador Retriever-Greyhound pedigree and in German Shepherd Dogs.
  
  
  CONCLUSIONS
  Multiple QTL were clearly involved with hip dysplasia. Identification of these QTL will enable fine-resolution mapping and subsequent assessment of candidate genes within the refined intervals to enable researchers to develop genetic screening tests and preventative and novel therapeutic regimens.
authors.affiliation: Center for Agricultural Biotechnology, Kasetsart University, Kamphaeng Saen, Nakhon Pathom, Thailand.
authors.forename: Janjira
authors.initials: J
authors.lastname: Phavaphutanon
authors.forename: Raluca G
authors.initials: RG
authors.lastname: Mateescu
authors.forename: Kate L
authors.initials: KL
authors.lastname: Tsai
authors.forename: Peter A
authors.initials: PA
authors.lastname: Schweitzer
authors.forename: Elizabeth E
authors.initials: EE
authors.lastname: Corey
authors.forename: Margaret A
authors.initials: MA
authors.lastname: Vernier-Singer
authors.forename: Alma J
authors.initials: AJ
authors.lastname: Williams
authors.forename: Nathan L
authors.initials: NL
authors.lastname: Dykes
authors.forename: Keith E
authors.initials: KE
authors.lastname: Murphy
authors.forename: George
authors.initials: G
authors.lastname: Lust
authors.forename: Rory J
authors.initials: RJ
authors.lastname: Todhunter
mesh_terms: D000818:Animals; D004247:DNA / Q000235:genetics / Q000302:isolation & purification; D004283:Dog Diseases / Q000235:genetics*; D004285:Dogs; D005260:Female; D005838:Genotype; D006619:Hip Dysplasia, Canine / Q000235:genetics*; D006621:Hip Joint / Q000473:pathology; D008098:Litter Size; D008297:Male; D018895:Microsatellite Repeats / Q000235:genetics; D010375:Pedigree; D010641:Phenotype; D040641:Quantitative Trait Loci; D013045:Species Specificity
chemical_list: D004247:DNA