This has for instance been observed for the MSH2 gene in families with Lynch syndrome [25], and, interestingly, in chronic lymphocytic leukemia (CLL) allele-specific expression of DAPK1 has been shown to occur in non-malignant cells in more than 10% of CLL cases but not in a healthy control population. This evidence concerns the gene MSH2 and B-cell chronic lymphocytic leukemia.