A decade in search of myopia genes

Abstract

Nearly half of visual impairment in the world is caused by uncorrected refractive errors, and myopia constitutes a significant proportion of this problem. Moreover, the prevalence of myopia is increasing, especially in Asian countries. Linkage studies have identified at least 18 possible loci (MYP) in 15 different chromosomes associated with myopia, although some of these remain to be confirmed. However, when studies have been carried out to identify specific candidate genes, it is apparent that these genes are often not part of MYP loci. In studying the expression of specific genes that might be responsible for myopia, we are learning that the involvement of various small leucine-rich repeat proteoglycans and growth factors is not a simple one. The emerging picture is one of complex interaction, in which mutations in several genes likely act in concert. The majority of myopia cases are not likely caused by defects in structural proteins, but in defects involving the control of structural proteins. The future of genetic research in this area will likely rely increasingly on microchip array technology.

Recent trends in the management of maculopathy secondary to pathological myopia

“…The pathogenesis of high myopia is unknown. Twin studies have estimated high trait heritabilities, and genetic and environmental susceptibility factors have been demonstrated to play an important role in its development [11,12]. Myopic maculopathy describes a spectrum of clinical changes that comprise the main cause of visual loss among highly myopic individuals.…”

Prevalence of refractive errors in the European adult population: the Gutenberg Health Study (GHS)

“…Although there is evidence that refractive errors among siblings correlate closely,12 the genetic background of myopia remains unclear, as it may involve a complex interaction of multiple genes 13. Environmental associations have also been described between myopia and urban environment as well as with higher education 6…”

Myopic Maculopathy: A Review

“…Instead of myopia being caused by a defect in a structural protein, defects in the control of these structural proteins might be the actual cause of myopia [81]. …”

“…Taken together, observational and experimental studies have revealed the complex nature of human refractive variation, which likely involves variants in several genes and functional pathways. Multiway interactions between genes and/or environmental factors may also be important in determining individual risks of myopia, and may help explain the complex pattern of refractive error in human populations [81]. …”