Inherited retinal dystrophies (IRDs) are a broad group of clinically and genetically heterogeneous rare eye diseases resulting in progressive visual impairment or blindness. The phenotype-genotype correlations established in present study may improve clinical diagnosis of affected individuals for better management and counseling. Ser2445Phe) with USH2 phenotype in another Pakistani family. This study provided first evidence for association of a novel USH2A variant with KC phenotype in a Pakistani family as well as established the phenotype-genotype correlation of a USH2A variant (c.7334 C > T, p. Moreover, the USH2A variants were predicted to be deleterious or potentially disease causing by PolyPhen-2, PROVEAN and SIFT. These variants were not detected in ethnically matched healthy controls.

Homozygosity of identified missense USH2A variants was found associated with autosomal recessive inherited KC and USH2 phenotypes in investigated families. Ser2445Phe) in the USH2A gene was found segregating in another Pakistani family with USH2 phenotype. In addition, a missense variant (c.7334 C > T, p. A novel variant c.4029T > G, p.Asn1343Lys in the USH2A gene was detected in a Pakistani family with KC phenotype. Resultsĭisease causing variants in the USH2A gene were identified in two families displayed KC and USH2 phenotypes. We performed direct Sanger sequencing and co-segregation analysis of the USH2A gene to identify disease causing variants in a non-syndromic RP family, two USH2 families and two Keratoconus (KC) families.

This study aimed to determine the causative role of the USH2A gene in autosomal recessive inherited ocular diseases and to establish genotype-phenotype correlation associated with USH2A variants. Mutations in the USH2A gene cause a significant proportion of recessive non-syndromic RP and USH type II (USH2). The most common form of syndromic RP is Usher syndrome (USH) accounting for approximately 20–30 % of RP cases. Retinitis pigmentosa (RP) is the most common inherited retinal dystrophy, affecting approximately 1 in 4000 individuals worldwide.

Usher syndrome gene reviews