A pathogenic variant in the transforming growth factor beta I (TGFBI) in four Iranian extended families segregating granular corneal dystrophy type II: A literature review
نویسندگان
1 Department of Genetics, Islamic Azad University, Science and Research Branch, Tehran , Iran
2 Department of Ophthalmology, Birjand University of Medical Science, South Khorasan, Iran
3 Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
4 Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
5 Zeiss Ophthalmology Clinic, Tabas, South Khorasan, Iran
6 Social Detrimental Health Center, Birjand University of Medical Science, South Khorasan, Iran
doi
10.22038/ijbms.2020.36763.8757چکیده
Objective(s): Granular and lattice corneal dystrophies (GCDs & LCDs) are autosomal dominant inherited disorders of the cornea. Due to genetic heterogeneity and large genes, unraveling the mutation is challenging.Materials and Methods: Patients underwent comprehensive clinical examination, and targeted next-generation sequencing (NGS) was used for mutation detection. Co-segregation and in silico analysis was accomplished.Results: Patients suffered from GCD. NGS disclosed a known pathogenic variant, c.371G>A (p.R124H), in exon 4 of TGFBI. The variant co-segregated with the phenotype in the family. Homozygous patients manifested with more severe phenotypes. Variable expressivity was observed among heterozygous patients. Conclusion: The results, in accordance with previous studies, indicate that the c.371G>A in TGFBI is associated with GCD. Some phenotypic variations are related to factors such as modifier genes, reduced penetrance and environmental effects.
