MULTIPLE CONGENITAL OCULARANOMALIES IN ICELANDICHORSES By Mareli Ots
MULTIPLE CONGENITAL OCULARANOMALIES (MCOA) A hereditary eye defect. First described in Silver colored Rocky Mountain horses. Is caused by the mutation which contains the gene and the mutation that is associated with the Silver coat color (PMEL 17).
THE AIM OF THE RESEARCH Ocular defects are caused by the mutation which is restricted to horses who are related to the Rocky Mountain Horse breed. Scientists examined another horse breed (the Icelandic horse) to disprove that. Icelandic horse is historically divergent from Rocky Mountain horses.
RESULTS 24 Islandic horses were examined. 4 of them had the MCOA-phenotype and they were homozygous for the PMEL17 mutation. 14 horses were heterozygous for the PMEL17 mutation and they had the Cyst-phenotype. Three horses were genotyped as PMEL17 heterozygotes but cysts or other forms of anomalies were unable to detect.
IRIDAL ABNORMALITIES AND CATARACTS IN THEMCOA-PHENOTYPE
CONCLUSION New facts about the syndrome. The syndrome is segregating with the PMEL17 mutation in the Icelandic Horse population. Important in breeding decisions. MCOA syndrome is present in breeds that are more ancient and not closely related to the Rocky Mountain Horse breed.
REFERENCES BMC Veterinary Research. 2011. “Multiple congenital ocular anomalies in Icelandic horses”. Available at http://www.biomedcentral.com/1746- 6148/7/21#B1