Most microsatellite unstable sporadic colorectal carcinomas carry MBD4 mutations

The MBD4 gene is involved in the repair of mutation at methyl-CpG dinucleotides. In microsatellite unstable tumours MBD4 can itself be mutated at an exonic polynucleotide tract. By analysing DNA from microdissected tumour samples we have found that both frequency and pattern of mutation are more significant than originally reported.