Clinical and molecular features of familial and sporadic cases of von Hippel-Lindau disease from Mexico.
BACKGROUND
von Hippel-Lindau disease (VHL) is an uncommon autosomal dominant condition predisposing to the development of tumours in a variety of body organs and caused by germline mutations in VHL, a tumour suppressor gene located on 3p. Up to 60% of VHL patients show ocular involvement with retinal hemangioblastoma being the most common observed lesion. In this study, we describe the clinical and genetic characteristics of two familial and one apparently non-familial case of VHL ascertained at our institution.


METHODS
Clinical evaluation included ophthalmologic examination and imaging exams for tumours identification; molecular analysis consisted of PCR amplification of the complete VHL gene coding sequence (three exons) and automated nucleotide sequencing.


RESULTS
A total of eight affected subjects were demonstrated to carry a causative mutation in VHL. Affected subjects from family #1 had a c.245G > C change, predicting a p.R82P substitution, affected individuals from family #2 were shown to have a c.266T > C change, leading to a p.L89P missense substitution, whereas the apparently non-familial case had a c.298-299insA mutation. One subject from family #2 was a non-penetrant carrier. No ocular anomalies were found in two adult affected subjects carrying the p.L89P mutation.


CONCLUSIONS
Considerable interfamilial and intrafamilial clinical variability as well as one instance of non penetrance were recorded in these VHL disease cases. Three different mutations were demonstrated, including the c.298-299insA one base insertion, which has been previously described in two unrelated families from our country. Although additional studies are needed, our data suggest that this insertion could be a 'founder' mutation.
Chacon-Camacho
Oscar F
OF
Department of Genetics, Institute of Ophthalmology 'Conde de Valenciana', Mexico City, Mexico.
Rodriguez-Dennen
Fernando
F
Camacho-Molina
Alejandra
A
Rasmussen
Astrid
A
Alonso-Vilatela
Elisa
E
Zenteno
Juan C
JC
D000328:Adult; D019943:Amino Acid Substitution; D002292:Carcinoma, Renal Cell / Q000235:genetics; D016543:Central Nervous System Neoplasms / Q000235:genetics; D002893:Chromosomes, Human, Pair 3; D003596:Cytosine; D005190:Family; D005260:Female; D006147:Guanine; D006801:Humans; D007680:Kidney Neoplasms / Q000235:genetics; D008297:Male; D008800:Mexico; D008875:Middle Aged; D009154:Mutation; D010375:Pedigree; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D051794:Von Hippel-Lindau Tumor Suppressor Protein / Q000235:genetics*; D006623:von Hippel-Lindau Disease / Q000235:genetics*
D006147:Guanine; D003596:Cytosine; D051794:Von Hippel-Lindau Tumor Suppressor Protein; C497446:VHL protein, human