Detection of mutations of the RB1 gene in retinoblastoma patients by using exon-by-exon PCR-SSCP analysis.
Most sporadic cases of retinoblastoma, malignant eye tumor of children, may require the identification of a mutation of the retinoblastoma gene (RB1 gene) for precise genetic counseling. We established a mutation detection system of and screened for the RB1 gene mutation in 24 patients with retinoblastoma--12 bilateral patients and 12 unilateral patients. Mutation analysis was performed by PCR-mediated SSCP analysis in the entire coding region and promoter region, as an initial screening method, followed by direct genomic sequencing. Possible oncogenic mutations were identified in 14 (58%) of 24 tumors, of which 6 were single base substitutions, 4 were small deletions, 3 were small insertions, and 1 was a complex alteration due to deletion-insertion. A constitutional somatic mosaicism was suggested in one bilateral patient. A majority (57%) of mutations were found in E1A binding domains, and all were presumed to truncate the normal gene products. The mutation analysis presented here may provide a basis for the screening system of RB1 gene mutations in retinoblastoma patients.
Shimizu
T
T
Radiation Biology Center, Kyoto University, Japan.
Toguchida
J
J
Kato
M V
MV
Kaneko
A
A
Ishizaki
K
K
Sasaki
M S
MS
D001483:Base Sequence; D002478:Cells, Cultured; D002872:Chromosome Deletion; D002874:Chromosome Mapping; D002882:Chromosomes, Human, Pair 13; D004252:DNA Mutational Analysis; D017931:DNA Primers; D005091:Exons; D005134:Eye Neoplasms / Q000235:genetics*; D005347:Fibroblasts / Q000378:metabolism; D016161:Genes, Retinoblastoma; D006801:Humans; D008969:Molecular Sequence Data; D017354:Point Mutation; D016133:Polymerase Chain Reaction; D015183:Restriction Mapping; D012175:Retinoblastoma / Q000235:genetics*; D012867:Skin / Q000378:metabolism
D017931:DNA Primers