A novel variant in TGFBI causes keratoconus in a two-generation Chinese family

Background This study aims to investigate the genetic abnormalities in a two-generation Chinese family affected by keratoconus (KC). A two-generation Chinese family affected by KC was studied. Materials and Methods A total of 118 unrelated healthy individuals without KC were recruited as controls. The family history, clinical data, and peripheral blood leukocytes were collected from all subjects. Whole exome sequencing was performed using the genomic DNA of the proband (II.2) and the other two affected family members (I.1 and II.3). Afterwards, polymerase chain reaction was performed for the other enrolled subjects to verify the variants identified in family members with KC. The PolyPhen2, SIFT, PROVEIN and Mutation Taster software programs were applied to analyze the functional consequences of the variants. Results A single nucleotide polymorphism (VARIANT) (c.1406 G > A [rs759370852]) in the transforming growth factor beta-induced (TGFBI) gene was identified in all affected family members, which resulted in a p.R469H amino acid change. This variant was not detected in the controls. The variant c.1406 G > A in TGFBI was predicted as probably damaging with software programs. Conclusion A novel variant c.1406 G > A in TGFBI has been identified, and probably contributes to the pathogenesis of KC.