Aneuploidy of lymphocytes in familial polyposis coli

The "in vitro" aneuploidy of peripheral lymphocytes in 13 members of a family affected by familial polyposis coli and in 5 patients affected by familial adenomatosis and belonging to other two families, was examined. The increase in aneuploidy of lymphocytes was significant only in 6 of the 13 members of the family (2 affected by polyposis and 4 not affected) and in all 5 patients with polyposis. Aneuploidy could be, for these reasons, a marker for polyposis.