Genome-wide search for markers associated with osteochondrosis in Hanoverian warmblood horses.

The research article details a genome-wide scan performed to identify loci related to osteochondrosis and osteochondrosis dissecans in the breed of Hanoverian warmblood horses, and made significant discoveries on four equine chromosomes.

Research Objective and Methodology

• The primary objective of this research was to identify the quantitative trait loci (QTLs) for osteochondrosis (OC) and osteochondrosis dissecans (OCD) in horses, particularly in Hanoverian warmblood horses.
• The researchers conducted a genome-wide scan and involved 260 microsatellites which are specific locations on chromosomes that help track the inheritance of traits.
• The sample data was drawn from 211 Hanoverian warmblood horses and the horses comprised 14 paternal half-sib families. The traits under study were OC and OCD, affecting either the fetlock or hock joints of the horses.

Research Procedure and Findings

• The research executed in two steps included a first scan with 172 microsatellite markers.
• In the subsequent step, 88 additional markers were employed to further refine the initial locus identified.
• The results revealed significant QTLs located on equine chromosomes 2, 4, 5, and 16. Interestingly, the researchers discovered that QTLs for OC in both fetlock and hock joints overlapped on the same chromosomes. This finding suggests a possible genetic relationship between these traits.

Further Findings and Conclusion

• The study found that QTLs reached the chromosome-wide significance level on eight different equine chromosomes: 2, 3, 4, 5, 15, 16, 19, and 21.
• This research is a key starting point in the identification of candidate genome regions that could possibly contain genes responsible for equine OC.
• However, the researchers emphasized that further investigations are necessary in order to refine the map positions of the QTLs identified for OC.