Mutational analysis of N-ras , p53 , CDKN2A ( p16 INK4a ), p14 ARF , CDK4 , and MC1R genes in human dysplastic melanocytic naevi

In order to detect possible dysplastic melanocytic naevi (DMN) associated melanoma risk factors and lesion specific differences in the mutation spectrum of dysplastic and congenital melanocytic naevi (CMN), we screened 19 specimens of human sporadic DMN derived from 19 patients for the presence of mutations in five genes, which we had investigated in a former study in 19 CMN1 and which have been reported to be associated with human cutaneous melanoma ( N-ras ,2 p53 ,3 CDKN2A ,4 CDK4 ,5 and MC1R 6,7). DNA was extracted from selected paraffin embedded DMN resection specimens using the QIAamp DNA Mini Kit (Qiagen) according to the recommendations of the supplier. The relative number of atypical melanocytes in the DMN and the histological subtype of the DMN were determined in parallel slides by an experienced dermatologist (Dr Regina Zimmermann) (table 1). View this table: Table 1 N-ras mutations and MC1R variants in human spontaneous dysplastic naevi The screening strategy for the detection of activating point mutations in the oncogenes N-ras and CDK4 as well as for germline sequence variants in the MC1R gene by combined RFLP-PCR/SSCP analysis, and the screening strategy for the detection of homozygous deletions and point mutations in the tumour suppressor genes p53 and CDKN2A by combined multiplex-PCR/SSCP analysis, have been described previously.1 In order to …