MED21 and Cafe-au-lait spot: Thus, we identified the coding and limited intronic nucleotide sequence of the following genes in germline DNA: MSH6, MSH2, MLH1, MED21 and DPH2. We sequenced MSH6 and MED21 genes because of their highly significant association with CALM count in both microarray and qPCR experiments, and because germline mutations in MSH6 have been associated with development of café-au-lait macules in non-NF1 patients.