Familial melanoma (MLM) is sometimes found associated with the dysplastic nevus syndrome (DNS). Considerable controversy exists over the possible assignment of a cutaneous malignant melanoma/dysplastic nevus gene, designated CMM, to the distal short arm of chromosome 1, linked to the PND and D1S47 loci. To date, no support for linkage of MLM alone to these markers has been found; likewise no study has been able to exclude the entire region between PND and D1S47 from linkage to MLM. We have carried out linkage studies between markers on 1p and MLM in seven Australian kindreds; three of these are the largest reported worldwide. We have been able to exclude localization of an MLM gene from a 40-cM region that spans the interval between D1S47 and PND and extends approximately 15 cM on either side of these markers. In addition, we can exclude a region of about 20 cM around the MYCL1/D1S57 loci.