Investigation of germline variants in Iranian patients with retinal capillary hemangioblastoma and genotype-phenotype analysis.

BACKGROUND

Retinal capillary hemangioblastoma (RCH), while sporadic in some cases, is the most common and earliest manifestation of von Hippel-Lindau disease (VHL). This is the first report on different types of VHL variants and genotype-phenotype correlations in Iranian families with RCH.

MATERIALS AND METHODS

In this prospective observational case series study, 17 families with RCH were included. PCR was performed to amplify 3 exons of VHL gene. Afterward, Sanger sequencing was performed on all PCR products. For the detection of VHL copy number variations, MLPA was used.

RESULTS

Our study identified 10 different types of VHL variants. Missense mutations were the most common variants found and affected the structure of α domain of the VHL protein (pVHL). The majority of mutations (72.7%) in the patients with RCH and central nervous system hemangioblastoma (CNS-HB) were located on α domain.

CONCLUSION

α domain of VHL may play a potential role in the pathogenesis of RCH. Our findings suggest that genotype-phenotype characteristics in those variants in α- domain may predispose patients to RCH with CNS-HB.