Abstract
Some properties ofin vitro growth associated with transformation, varied between and within the clinically defined colonic cancer syndromes. None of these differences, nor any grouping of them, permitted identification of specific genotypes. Such differences did support the concept, long assumed on the basis of differences in extracolonic lesions in some colonic cancer syndromes, that they are not all due to the same mutation but represent distinct genetic entities, these genetic differences not being detectablein vivo, but ratherin vitro.