A single genetic test can identify the presence and cause of mismatch repair deficiency Researchers have developed a new integrated genetic/epigenetic DNA-sequencing protocol known as MultiMMR that can identify the presence and cause of mismatch repair (MMR) deficiency in a single test from a small sample of DNA in colon, endometrial, and other cancers. This alternative to complex, multi-step testing workflows can also determine causes of MMR deficiency often missed by current clinical tests. Their results are presented in the Journal of Molecular Diagnostics, published by Elsevier. MMR genes monitor and repair errors that can occur in normal cell replication and recombination. In some inherited and acquired cancers, one or more of the MMR genes are deactivated. "The impact of MultiMMR is broad. Tumors with MMR deficiency respond well to new cancer immunotherapies," explains lead investigator Trevor J. Pugh, PhD, Department of Medical Biophysics, University of Toronto; Princess Margaret Cancer Centre, University Health Network; and Ontario Institute for Cancer Research, Toronto, ON, Canada. "Determining whether an individual has an inherited form of MMR deficiency can also allow clinicians to enroll patients in active surveillance, engage in risk-reduction strategies, and provide genetic testing to relatives - potentially improving patient outcomes."