Abstract
Purpose::
Myopia is the most common of all ocular conditions. The etiology of myopia is not known, both genetic and environmental factors seem to play a role. In high myopia, genetic factors appear to play a predominant role. The purpose of this study is to map a gene(s) responsible for high myopia in a Polish population.
Methods::
To date, we have carefully examined, collected blood and purified DNA from 310 individuals with high myopia (<-6 diopters) from 61 unrelated families in Poland. The preliminary genotyping was conducted in 23 families. Prior to preceding with the targeting genotyping, linkage to markers for the myopic genetic syndromes of Stickler syndrome types I, II and III; Marfan syndrome, Knobloch syndrome and juvenile glaucoma were tested. Next, genotyping of high myopia associated loci [7q36 (MYP4), 12q21-23 (MYP3), 18p11.31 (MYP2), and 17q21-23 (MYP5), 2q37, 4q22-4q27, 10q] and MYP6 locus [mild/moderate myopia, 22q12] was performed. Next, we performed genome wide screen with fluorescent markers with an average spacing of 8 cM spanning all chromosomes.
Results::
In Polish population familial high myopia seems to segregate in an autosomal dominant fashion. Linkage to Stickler syndrome, Marfan syndrome, Knobloch syndrome and juvenile glaucoma loci were excluded. We excluded previously assigned high myopia loci and performed a genome-wide screen for a high myopia locus.
Conclusions::
We have identified, collected and characterized a large cohort of polish families with high myopia and excluded the principal genetic cause of this phenotype. These families will be instrumental in identifying one or more locus for genetic high myopia.
Keywords: gene mapping • myopia • linkage analysis