Screening of neurofibromatosis type 1 gene: identification of a large deletion and of an intronic variant.
Neurofibromatosis type 1 of von Recklinghausen is a common autosomal dominant disorder, characterized by peripheral neurofibromas, café-au-lait spots and Lisch nodules of the iris. The high mutation rate at the neurofibromatosis type 1 locus results in a wide range of molecular abnormalities. We have screened seven different exons of the neurofibromatosis type 1 gene, including those codifying for the GAP-related domain, using the RNA-Single Strand Conformation Polymorphism (RNA-SSCP) method in a series of 59 neurofibromatosis type 1 patients. We have also analyzed four intragenic repeats and one RFLP to detect hemizygosity and evaluate informativeness in at-risk families. One deletion and a new intronic normal variant have been detected. Thus the majority of Neurofibromatosis type 1 chromosomes have not been characterized, confirming difficulty in providing proper genetic counselling in neurofibromatosis type 1 families, even following extensive DNA analysis.
Grifa
A
A
Servizio di Genetica Medica, IRCCS-Ospedale CSS, San Giovanni Rotondo, Italy.
Piemontese
M R
MR
Melchionda
S
S
Origone
P
P
Zelante
L
L
Coviello
D
D
Fratta
G
G
Dallapiccola
B
B
Balestrazzi
P
P
Ajmar
F
F
D000483:Alleles; D001483:Base Sequence; D004252:DNA Mutational Analysis; D004276:DNA, Satellite / Q000235:genetics; D005091:Exons; D005260:Female; D016514:Genes, Neurofibromatosis 1 / Q000235:genetics*; D014644:Genetic Variation; D006579:Heterozygote; D006801:Humans; D007438:Introns / Q000235:genetics*; D008297:Male; D008969:Molecular Sequence Data; D010375:Pedigree; D012150:Polymorphism, Restriction Fragment Length; D018807:Polymorphism, Single-Stranded Conformational; D012313:RNA / Q000737:chemistry; D012091:Repetitive Sequences, Nucleic Acid; D017384:Sequence Deletion
D004276:DNA, Satellite; D012313:RNA