Five one- and two-base repeat loci were tested for instability, comparing cancer tissue to reference normal tissue from the same patient. Three of the five loci showed additional alleles in the cancer cells compared to the normal cells. How is this interpreted?

Question

Quizplus · Accepted Answer

The presence of additional alleles in the cancer cells compared to the normal cells indicates that there is high instability, which is characterized as MSI-H (high microsatellite instability). Two or more of the markers must display additional alleles to be classified as MSI-H.

Five One- and Two-Base Repeat Loci Were Tested for Instability