Genetic study of a large Chinese kindred with von Hippel-Lindau disease.

BACKGROUND

Von Hippel-Lindau (VHL) disease is a heraditary cancer syndrome caused by germline mutations of the VHL tumor on the suppressor gene. This study was to show the clinical characteristics of a large Chinese kindred with von Hippel-Lindau disease and to evaluate the role of the genetic test of VHL disease in the diagnosis of VHL disease and clinical screening of members of the VHL disease family.

METHODS

DNA extracted from peripheral blood was amplified by PCR to three exons of the VHL gene in 27 members of a large kindred with VHL disease. PCR products were directly sequenced. The involvements of multi-organs in the kindred with VHL disease were confirmed by history taking and radiography.

RESULTS

Of 47 members in the four generations of the kindred, 18 members were diagnosed as having VHL disease. Clinical manifestations of 18 patients included: central nervous system (CNS) hemangioblastoma (5), renal cell carcinoma and CNS hemangioblastoma (3), renal cell carcinoma and retinal angioma (3), renal cell carcinoma and multiple pancreatic cysts (1), renal cell carcinoma and retinal angioma and multiple pancreatic cysts (2), renal cell carcinoma and CNS hemangioblastomas and multiple pancreatic cysts (1), and multiple pancreatic cysts and multiple renal cysts (1), multiple pancreatic cysts (2). The common lesions of the 18 patients were renal cell carcinoma (55.6%), CNS hemangioblastoma (50.0%), retinal angioma (27.8%), and multiple pancreatic cysts (38.9%). Among the 27 members who volunteered for genetic analysis, 15 members including 9 affected family patients and 2 asymptomatic patients and 4 carriers, who are still alive, presented a codon 78 from Asn to Ser change at nucleotide 446 (A-->G) in exon 1. Four members were carriers with the same VHL gene mutation. Two asymptomatic patients were initially diagnosed by genetic testing and subsequently confirmed radiologically and surgically. Members without gene mutation had no clinical evidence of VHL disease.

CONCLUSIONS

The large Chinese kindred with VHL disease was classified as type I. The main characteristics in the kindred were higher incidence of renal cell carcinoma and lower incidence of retinal angioma. Genetic test plays an important role in early detecting asymptomatic patients and the carriers in clinical screening of members of the families with VHL disease. It is also important to prevent the transmission of VHL disease to their offsprings in the kindred.