Alternative titles; symbols
DO: 11830; MONDO: 0012021;
Cytogenetic location: 7p15 Genomic coordinates (GRCh38) : 7:20,900,001-28,800,000
| Location | Phenotype |
Phenotype MIM number |
Inheritance |
Phenotype mapping key |
|---|---|---|---|---|
| 7p15 | Myopia 17 | 608367 | Autosomal dominant | 2 |
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.
Naiglin et al. (2002) performed linkage analysis in 21 French and 2 Algerian families with autosomal dominant high-grade myopia (refractive error greater than or equal to -6.00 diopters). They excluded previously identified myopia loci and found suggestive evidence of linkage to chromosome 7q36, with a maximum multipoint lod score of 2.81. No locus heterogeneity was detected.
Paget et al. (2008) studied 26 families segregating high-grade myopia, including the families reported by Naiglin et al. (2002) and a subset of 9 newly collected families. A genomewide scan of the 9 new families showed no linkage to 7q36. Study of all 26 families with a parametric model did not yield a significant lod score (greater than 3), even for 7q36. However, a nonparametric model demonstrated significant linkage to chromosome 7p15 in all of the families (Z-NPL = 4.07, p = 0.00002). The interval was 7.81 cM between markers D7S2458 and D7S2515.
Ciner et al. (2008) performed quantitative trait locus linkage analysis in African American families to identify genomic regions responsible for ocular refraction. They genotyped for 387 microsatellite markers in 398 individuals with a mean refraction of -2.87 diopters and at least 1 diopter in 267. Linkage was identified on chromosome 7p15 (maximum lod of 5.87) in a 17-Mb region between markers D7S1808 and D7S817. The authors noted that a previous study in European-derived families by Klein et al. (2007) had found evidence of linkage to chromosome 7p21.
Because Paget et al. (2008) found no evidence of linkage of myopia to chromosome 7q36, as had been reported by Naiglin et al. (2002), but instead found significant linkage to 7p15, the symbol MYP4 was originally used for the locus on 7p15. The study by Paget et al. (2008) included the families reported by Naiglin et al. (2002).
Ciner, E., Wojciechowski, R., Ibay, G., Bailey-Wilson, J. E., Stambolian, D. Genomewide scan of ocular refraction in African-American families shows significant linkage to chromosome 7p15. Genet. Epidemiol. 32: 454-463, 2008. [PubMed: 18293391] [Full Text: https://doi.org/10.1002/gepi.20318]
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.
Klein, A. P., Duggal, P., Lee, K. E., Klein, R., Bailey-Wilson, J. E., Klein, B. E. K. Confirmation of linkage to ocular refraction on chromosome 22q and identification of a novel linkage region on 1q. Arch. Ophthal. 125: 80-85, 2007. [PubMed: 17210856] [Full Text: https://doi.org/10.1001/archopht.125.1.80]
Naiglin, L., Gazagne, C., Dallongeville, F., Thalamas, C., Idder, A., Rascol, O., Malecaze, F., Calvas, P. A genome wide scan for familial high myopia suggests a novel locus on chromosome 7q36. J. Med. Genet. 39: 118-124, 2002. [PubMed: 11836361] [Full Text: https://doi.org/10.1136/jmg.39.2.118]
Paget, S., Julia, S., Vitezica, Z. G., Soler, V., Malecaze, F., Calvas, P. Linkage analysis of high myopia susceptibility locus in 26 families. Molec. Vis. 14: 2566-2574, 2008. [PubMed: 19122830]