DO: 11830;
| Location | Phenotype |
Phenotype MIM number |
Inheritance |
Phenotype mapping key |
Gene/Locus |
Gene/Locus MIM number |
|---|---|---|---|---|---|---|
| 4q35.1 | Myopia 22, autosomal dominant | 615420 | Autosomal dominant | 3 | CCDC111 | 615421 |
A number sign (#) is used with this entry because of evidence that myopia-22 (MYP22) is caused by heterozygous mutation in the CCDC111 gene (615421) on chromosome 4q35.
Myopia, or nearsightedness, is a refractive error of the eye. Light rays from a distant object are focused in front of the retina and those from a near object are focused in the retina; therefore distant objects are blurry and near objects are clear (summary by Kaiser et al., 2004).
For a discussion of genetic heterogeneity of susceptibility to myopia, see 160700.
Zhao et al. (2013) studied a 4-generation Chinese family segregating autosomal dominant high myopia. The proband was a woman who had painless progressive deterioration of bilateral vision from age 20 years; she presented at 50 years of age because she could not see objects clearly due to cataracts. Examination showed that for both eyes unaided visual acuity was less than 0.01 and refractive error was -20.00 D. The axial length was 33.69 mm for the right eye and 33.50 mm for the left. Seven additional family members were diagnosed with high myopia, with vision loss and refractive errors from -6.75 D to -11.00 D. None of the affected family members had any other clinical abnormalities.
In a 4-generation Chinese family with autosomal dominant high myopia, Zhao et al. (2013) performed exome sequencing and identified a missense mutation in the CCDC111 gene (Y89D; 605421.0001) that segregated with disease in the family and was not found in 270 Chinese controls. The proband, who had a more severe myopia than her children, was homozygous for the mutation, whereas all other affected family members were heterozygous. Screening of the CCDC111 gene in an additional 270 sporadic myopia patients identified 4 more patients with a heterozygous Y89D mutation. Because the severity of the clinical phenotype varied among the affected individuals, Zhao et al. (2013) suggested that environmental influences likely contributed to the etiology in the family and sporadic patients.
Kaiser, P. K., Friedman, N. J., Pineda, R., II. The Massachusetts Eye and Ear Infirmary Illustrated Manual of Ophthalmology. Vol. 2. Philadelphia : Saunders , 2004. P. 457.
Zhao, F., Wu, J., Xue, A., Su, Y., Wang, X., Lu, X., Zhou, Z., Qu, J., Zhou, X. Exome sequencing reveals CCDC111 mutation associated with high myopia. Hum. Genet. 132: 913-921, 2013. [PubMed: 23579484] [Full Text: https://doi.org/10.1007/s00439-013-1303-6]