These findings support a model where somatic instability of the (A)8 tract produced by the APC I1307K allele leads to increased APC gene inactivation and directly accounts for 42% of the colorectal neoplasms occurring in APC I1307K carriers.
The I1307K mutation is common among Jews who have had colorectal neoplasms, but overall it was found to have little effect clinically in the current study group.