A T to C mutation in the polypyrimidine tract of the exon 9 splicing site of the RB1 gene responsible for low penetrance hereditary retinoblastoma. Issue 5 (1st May 2002) - Lefévre, S H; Chauveinc, L; Stoppa-Lyonnet, D; Michon, J; Lumbroso, L; Berthet, P; Frappaz, D; Dutrillaux, B; Chevillard, S; Malfoy, B