Study of MYOC Gene Mutation in POAG Patients in Zahedan, Iran

The second cause of blindness in the world is glaucoma that begins with visual impairments and, in many cases, ends with irreversible visual loss. Primary open-angle glaucoma (POAG) is the most common type of glaucoma, which causes irreversible optic nerve damage in adults. Glaucoma shows an unknown etiology, but there is strong evidence regarding the role of genetic factors in disease establishment. For determination of the role of MYOC gene mutations in the development of POAG in Zahedan, Iran, screening of this gene was performed.

Forty-five POAG patients were recruited from Noor Pajoohan Shargh clinic and Al-Zahra Eye Hospital, Zahedan University of Medical Sciences, Zahedan, Iran. Three exons of the MYOC gene were amplified in five amplicons, using polymerase chain reaction (PCR). Then PCR products were sequenced using the ABI big dye ABI Prism 3700 instrument in forward and reverse directions with the same primers.

Five variations were found in POAG patients: two known variations (rs2075648 and rs2234926) in exon 1, one in exon 2 (rs58117216), and two variants (rs74315330 and rs146606638) in exon 3. They were not all associated with the disease status and are known as normal variants. However, there was a mutation in exon 3 (Gln297 His or CM081349) only in one patient which is known as the disease causing mutation in some populations [1].

Since most of POAG patients had no mutation in the MYOC gene, other genes might have been involved in the pathogenesis of the disease.