ABSTRACT
OBJECTIVE: The Von Hippel-Lindau syndrome (VHLD), an inherited neoplastic syndrome predisposing to central nervous system hemangioblastoma (CNS), pheochromocytoma (PCC), renal cell carcinoma(RCC), retinal hemangioma (RA) and renal cysts, is caused by mutations or deletions of the VHL tumor-suppressor gene. To assess VHL genotype-phenotype correlations with function of pVHL a gene mutation analysis of members in a Chinese family with non-syndromic PCCs and individuals with apparently sporadic pheochromocytoma (ASP) was performed. MATERIALS AND METHODS: DNA samples of 20 members from the Chinese family with non-syndromic PCCs and 41 patients with ASP were analyzed by polymerase chain reaction and direct sequencing, confirmed by Taqman probe. RESULTS: Three novel mutations (H125P, 623(?TTTGTtG) and R120T) were identified in the Chinese family and in 3 among 41 ASP patients. The mutations were all located in exon 2 of VHL gene encoding ß-domain of pVHL. The tumor type in H125P carriers and R120T carriers was VHL type 2C. And 623(?TTTGTtG) carriers presented VHL type 2B or type 2C. CONCLUSIONS: VHL gene abnormalities were identified in the Chinese family with non-syndromic PCCs and patients with APS, resulting in dysfunction of pVHL. H125P and R120T could be associated with VHL type 2C, while 623(?TTTGTtG) might be linked with VHL type 2B or type 2C. Not only is the genetic analysis helpful for early diagnosis and treatment of patients with VHLD, it is also benefitial for research into VHLD pathogenesis.
Subject(s)
Adrenal Gland Neoplasms/genetics , Asian People/genetics , Carrier Proteins/genetics , Genetic Predisposition to Disease/genetics , Mutation/genetics , Pheochromocytoma/genetics , Adolescent , Adult , Child , Cytoskeletal Proteins , DNA Mutational Analysis/methods , Female , Genetic Testing/methods , Humans , Male , Middle Aged , Molecular Chaperones , Pedigree , Young Adult , von Hippel-Lindau Disease/geneticsABSTRACT
OBJECTIVE: To carry out a genetic detection and analysis of Von Hippel-Lindau (VHL) gene in Chinese patients with sporadic pheochromocytoma. METHODS: DNA samples were extracted from peripheral blood cells and fresh pheochromocytoma specimens from 41 patients with sporadic pheochromocytoma were assayed by polymerase chain reaction and direct sequencing. The DNA samples of 50 healthy volunteers were extracted from peripheral blood as a control. The PCR products of exon 1, exon 2 and exon 3 were used for molecular analysis of the VHL gene. The genetic detection of family members of VHL gene mutations was also performed. RESULTS: One of mutations was located at nucleotide 572 (G-->C) in exon 2, presenting a codon 120 from arginine (R) to threonine (T). Tow small insertions were locatated at nucleotide 623T (TTTGTtG) in exon 2, leading to a frameshift mutation. There were also three carriers of G572C and three carriers of 623T (TTTGTtG) in family members of the three cases. CONCLUSION: There are some Chinese patients with sporadic pheochromocytoma with tumorigenic VHL gene mutations. It is recommended to use the genetic detection and analysis of VHL gene as a routine examination for patients with sporadic pheoehromoeytoma under the age of 50 years with questionable family history. The genetic detection and analysis of VHL gene may be useful as a marker for the diagnosis of hereditary pheochromocytoma.
Subject(s)
Adrenal Gland Neoplasms/genetics , Mutation , Pheochromocytoma/genetics , Von Hippel-Lindau Tumor Suppressor Protein/genetics , Adult , DNA Mutational Analysis , DNA, Neoplasm/genetics , Exons , Family , Female , Humans , Male , Middle Aged , PedigreeABSTRACT
OBJECTIVE: To detect the VHL gene mutations in a Chinese family with nonsyndromic pheochromocytoma. METHODS: Mutations of VHL gene were detected in a Chinese family with nonsyndromic pheochromocytoma. Five patients and fifteen relatives were involved in this study. Peripheral blood was collected and total genomic DNA was prepared for polymerase chain reaction (PCR). PCR products of all the three exons of VHL gene were purified and a direct gene sequence analysis was performed. RESULTS: All the five patients presented a codon 125 from Histidine (H) to Proline (P) change at nucleotide 587 (A --> C) in exon 2. Seven members of fifteen relatives were carriers with the same VHL gene mutation. Two carriers were detected with bilateral adrenal tumors and right renal cyst respectively by ultrasonic inspection. CONCLUSION: The novel VHL gene mutation detected in this kindred may be the causative gene. Genetic test can detect the carriers in an early period. It is recommended as a routine method of genetic test in nonsyndromic pheochromocytoma patients.