GENOTYPE-PHENOTYPE CORRELATIONS OF NEW CAUSATIVE APC GENE-MUTATIONS IN PATIENTS WITH FAMILIAL ADENOMATOUS POLYPOSIS

Nine new causative mutations and seven previously characterised mutati ons of the APC gene of patients with familial adenomatous polyposis (F AP) were analysed for any genotype-phenotgrpe correlations. The only c lear genotype-phenotype correlation found was between the position of the mutation site and the presence or absence of congenital hypertroph y of the retinal pigment epithelium (CHRPE). A more distal mutation si te was associated with an earlier age of onset of symptoms and a large r number of colonic polyps, but a notable amount of intrafamilial vari ation was observed.