APC I1307K and E1317Q variants are rare or do not occur in Swedish colorectal cancer patients

Recently, a germ line mutation of the APC gene, I1307K, was discovered in a subset of Ashkenazi jews. The mutation involves an amino acid exchange and creates a tract consisting of eight contiguous adenosine residues believed to cause hypermutability in this region. Another germ line missense varian t, E1317Q, not restricted to a certain ethnic population, could functionall y alter the protein. These APC variants have been linked with increased col orectal cancer risk in several studies. However, they have not yet been inv estigated in Swedish colorectal cancer patients. Thus, our aim was to inves tigate the prevalence of I1307K and E1317Q in Swedish colorectal cancer pat ients in order to determine if these genetic Variants are important predisp osing factors to colorectal cancer in this population. To this end, sequenc e analysis was carried out of the APC gene in order to identify any I1307K and E1317Q variants in 106 unselected cases and 88 hereditary/familial colo rectal cancer cases including 22 cases of hereditary non-polyposis colorect al cancer (HNPCC) fulfilling the Amsterdam criteria. Out of a total of 194 cases examined, we did not find any variants. It seems that these alteratio ns are rare or absent in the Swedish population. (C) 2001 Elsevier Science Ltd. All rights reserved.