As part of an on-going genomic screen of unlinked Charcot-Marie-Tooth disease type 2 (CMT2) families, we identified 11 regions in the genome with lod scores > or = 1.0. One of these regions was near the recently identified CMTDI1 locus on 19q. We show evidence of linkage of DUK 1118 to this region and our data reduce the minimum candidate interval for CMTDI1 to the 9-cM interval spanned by D19S586 and D19S432. We also demonstrate that five additional CMT2 families are unlinked to 19q markers, providing further evidence of CMT2 heterogeneity.