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Von Hippel-Lindau (VHL) disease is a dominantly inherited familial cancer syndrome predisposing to a variety of malignant and benign neoplasms, most frequently retinal, cerebellar and spinal haemangioblastoma, renal cell carcinoma, phaeochromocytoma and pancreatic tumours. We have previously detected large germline deletions by Southern analysis and pulsed field gel electrophoresis in 19% and 3% of VHL patients respectively. We have now investigated 94 VHL patients without large deletions for intragenic mutations using single strand conformation polymorphism and heteroduplex analysis. Forty different mutations were identified in 55 unrelated kindreds. A wide variety of mutations were detected including missense (n = 19), nonsense (n = 6), frameshift deletions or insertions (n = 12), in frame deletions (n = 2) and a splice donor site mutation (n = 1). The two most frequent mutations, were missense mutations at codon 238 (Arg-->Gln and Arg-->Trp) and were detected in five and four unrelated kindreds, respectively. VHL disease shows marked phenotypic variability and although phaeochromocytoma occurs in only about 7% of patients, marked interfamilial differences are observed. We examined the relationship between VHL gene mutations and phenotype in 65 kindreds. Large deletions or intragenic mutations predicted to cause a truncated protein were found in 36 of 53 families without phaeochromocytoma but only two of 12 families with phaeochromocytoma (chi 2 = 8.58; P < 0.01). Of 12 families with phaeochromocytoma 10 had missense mutations compared with 13 of 53 kindreds without phaeochromocytoma (chi 2 = 12.33; P < 0.001). In particular, substitution of an arginine at codon 238 (Arg-->Trp or Arg-->Gln) was associated with a high risk (62%) of phaeochromocytoma.(ABSTRACT TRUNCATED AT 250 WORDS)

Molecular genetic analysis of five cases of 3p- syndrome (del(3)(qter-->p25:)) was performed to investigate the relationship between the molecular pathology and clinical phenotype. Fluorescence in situ hybridization studies and analysis of polymorphic DNA markers from chromosome 3p25-p26 demonstrated that all four informative cases had distal deletions. However, the extent of the deletion was variable: in two patients with the most extensive deletions the deletion breakpoint mapped between RAF1 and D3S1250, in one patient the deletion breakpoint was between D3S1250 and D3S601, and in two patients the deletion commenced telomeric to D3S601 (and telomeric to D3S1317 in one of these). All five patients displayed the classical features of 3p- syndrome (mental retardation, growth retardation, microcephaly, ptosis and micrognathia) demonstrating that loss of sequences centromeric to D3S1317 is not required for expression of the characteristic 3p- syndrome phenotype. The three patients with the most extensive deletions had cardiac septal defects suggesting that a gene involved in normal cardiac development is contained in the interval D3S1250 and D3S18. The PMCA2 gene is contained within this region and deletion of this gene may cause congenital heart defects. At least three patients were deleted for the von Hippel-Lindau (VHL) disease gene although none had yet developed evidence of VHL disease. We conclude that molecular analysis of 3p- syndrome patients enhances the management of affected patients by identifying those at risk for VHL disease, and can be used to elucidate the critical regions for the 3p- syndrome phenotype.

Von Hippel-Lindau disease is a dominantly inherited familial cancer syndrome characterised by the development of retinal angiomatosis, cerebellar and spinal hemangioblastoma, renal cell carcinoma, phaeochromocytoma and pancreatic tumours. A cDNA (g7) which detects frequent genomic rearrangements in VHL disease patients on Southern analysis, and contains the partial coding sequence of the VHL gene has been isolated recently. To characterise the nature of the genomic rearrangements in VHL disease we initially screened 116 patients with VHL disease and identified 22 patients (19%) with abnormal fragments in EcoR1 digested DNA probes with g7. We then established that the coding sequence contained within g7 is represented in 3 exons, and design exon specific probes to investigate the 22 patients with genomic rearrangements. All 22 patients were demonstrated to have germline deletions, but the deletions were heterogeneous with 7 patients having deletions confined to the 5' exon 1, and 8 with nonoverlapping deletions of exon 3. In 7 unrelated patients, including 2 new mutations, the germline deletions were similar in size and position. There was no relationship between the clinical phenotype and the deletion of individual exons. Although phaeochromocytoma was less frequent in kindreds with germline deletions than those without detectable deletions, the difference was not statistically significant (1/19 versus 16/72 respectively, chi 2 = 1.84 p > 0.1).

Von Hippel-Lindau (VHL) disease is a dominantly inherited familial cancer syndrome in which affected individuals have a greatly increased predisposition to the development of haemangioblastomas of the central nervous system and retina, renal cell carcinoma and phaeochromocytoma. The VHL gene has been mapped to chromosome 3p25-p26 by genetic linkage studies and we have previously demonstrated that the VHL gene is tightly linked to the D3S601 locus (Zmax = 18.86 at theta = 0.0) suggesting that D3S601 maps close to the VHL disease gene. We have constructed a long range physical map around D3S601 and screened 91 VHL patients from 80 kindreds for germline rearrangements using pulsed field gel electrophoresis. Two patients showed abnormal fragments in Mlul digested DNA probed with D3S601. Further analysis was consistent with both patients having germline deletions (approximately 120 kb and 50 kb) telomeric to D3S601. These results have (i) established the position of the VHL disease gene with respect to D3S601, (ii) refined the localisation of the VHL disease gene to a small region (approximately 50 kb) of chromosome 3p25-p26 and (iii) excluded the plasma membrane Ca(+)+-transporting ATPase isoform 2 (PMCA-2) gene as a candidate gene for VHL disease.

Von Hippel-Lindau (VHL) disease is a dominantly inherited familial cancer syndrome characterised by the development of retinal and central nervous system haemangioblastomas, renal cell carcinoma and phaeochromocytoma. The gene for VHL disease has been mapped to chromosome 3p25-p26 and presymptomatic diagnosis using linked DNA markers is available. We have previously mapped the VHL disease gene to a 4 cM interval between D3S1250 and D3S18. To increase access to presymptomatic diagnosis and to accelerate progress towards isolating the VHL disease gene we attempted to identify microsatellite DNA markers linked to the disease gene by genetic linkage analysis in 29 families. We found significant linkage between the VHL disease gene and dinucleotide (CA) repeat polymorphisms at D3S1038 (Zmax = 22.24 at theta = 0.01, CI 0.0001-0.06), D3S1110 (Zmax = 11.32 at theta = 0.07, CI 0.03-0.14) and D3S651 (Zmax = 7.73 at theta = 0.04, CI 0.008-0.13). We localised D3S1038 between D3S1250 and D3S601, and mapped D3S1110 and D3S651 centromeric to D3S1250. Multipoint linkage analysis mapped the VHL disease locus between D3S1038 and D3S18 with the maximum likelihood at D3S601. There was no evidence of locus heterogeneity. This study has (i) identified three microsatellite DNA markers in chromosome 3p25 linked to the VHL disease gene and (ii) narrowed the target region for the isolation of the VHL disease gene by positional cloning techniques. These findings will improve the management of families with VHL disease by improving the accuracy and availability of presymptomatic diagnosis using linked DNA markers, and will accelerate progress towards isolating the VHL disease gene.