Genome-wide SNP association-based localization of a dwarfism gene in Friesian dwarf horses
Orr, N.; Back, W.; Gu, J.; Leegwater, P.; Govindarajan, P.; Conroy, J.; Ducro, B.; Van Arendonk, J.A.M.; MacHugh, D.E.; Ennis, S.; Hill, E.W.; Brama, P.A.J.
Animal Genetics 41 Suppl. 2: 2-7
ISSN/ISBN: 0268-9146 PMID: 21070269 DOI: 10.1111/j.1365-2052.2010.02091.x
The recent completion of the horse genome and commercial availability of an equine SNP genotyping array has facilitated the mapping of disease genes. We report putative localization of the gene responsible for dwarfism, a trait in Friesian horses that is thought to have a recessive mode of inheritance, to a 2-MB region of chromosome 14 using just 10 affected animals and 10 controls. We successfully genotyped 34,429 SNPs that were tested for association with dwarfism using chi-square tests. The most significant SNP in our study, BIEC2-239376 (P(2df)=4.54 × 10(-5), P(rec)=7.74 × 10(-6)), is located close to a gene implicated in human dwarfism. Fine-mapping and resequencing analyses did not aid in further localization of the causative variant, and replication of our findings in independent sample sets will be necessary to confirm these results.