For individuals who have tested negative for MLH1, MSH2, or APC gene mutations, new genetic testing for these genes, called Southern blot, has become available. This test looks for gene changes where large portions of the gene may be missing or rearranged. These changes may be missed or undetectable on more traditional gene sequencing. Genetic testing for mutations in the MYH gene is also now available. Mutations in the MYH gene have recently been found in some colon polyp and cancer families.
In addition, testing for MSH6 is now available for families that tested negative for MLH1 and MSH2. It may be particularly useful for families with uterine cancer. If you have had genetic testing for hereditary colon cancer prior to November 2004 and have tested negative for MLH1 and MSH2, we encourage you to make an appointment with us for genetic counseling and testing. Please call the Clinical Genetics Service at 212-434-5149 to make an appointment for further testing.
