MLH1 and hereditary nonpolyposis colon cancer: Wijnen et al (1998) reported similar findings in the Dutch population; 6.5% of the HNPCC cases are due to intragenic deletion in MLH1 or MSH2. Genomic rearrangements are an important component of the MMR mutation spectrum, and Alu-mediated recombination are likely responsible of a large amount of these intragenic deletions (Nystrom-Lahti et al, 1995; Viel et al, 2002).