Isolation, characterization and molecular screening of canine SLC26A2 (sulphate transporter) in German Shepherd dogs with hip dysplasia

Abstract

The SLC26A2 gene codes for a sulphate transporter (the gene is also known as diastrophic dysplasia sulphate transporter gene; DTDST) and is a causative gene for human diastophic dysplasia due to undersulphation of proteoglycans in the cartilage matrix (Hastbacka et al. 1994). Several mutations in the SLC26A2 gene have been found in human diastrophic dysplasia (Hastbacka et al. 1994, 1996), achondrogenesis type IB (Superti-Furga 1994), and multiple epiphyseal dysplasia (Superti-Furga et al. 1999; Czarny-Ratajczak et al. 2001). Over 30 mutations in the SLC26A2 gene have been identified in human to date, including heterozygous single base deletions and splicing site mutations (Hastbacka et al. 1994, 1996; Superti-Furga et al. 1996, 1999; CzarnyRatajczak et al. 2001; Rossi and Superti-Furga 2001). Canine hip dysplasia is a developmental orthopedic disease in which an abnormal formation of the hip leads to looseness in the hip joints, causing cartilage damage (LaFond et al. 2002). Progressive arthritis can result, and when it does, it can be crippling. Hip dysplasia is not the same thing as arthritis in the hips, rather it is the most common cause of arthritis in the hips. Hip dysplasia is most common among larger breeds of dogs, especially German Shepherds, Rottweilers, Labrador Retrievers, Golden Retrievers, Mastiffs and Saint Bernards (Guilliard 2003). It is also seen in smaller breeds such as Cocker Spaniels and Springer Spaniels, as well as in mixed breeds (Guilliard 2003) Hip dysplasia is known to be transmitted genetically (Todhunter and Lust 2003), and recent genetic studies have found major genes for hip dysplasia in four Finnish dog populations (Maki et al. 2004), as well as quantitative trait loci (QTL) contributing to hip dysplasia in PortugueseWater Dogs (Chase et al. 2004). Further, the recent QTL mapping