Charcot-Marie-Tooth disease Type 1 (CMT) is an inherited neuropathy with known genetic heterogeneity, with at least one autosomal dominant form (CMT Type 1b) linked to the Duffy region of chromosome 1. Autosomal dominant families not demonstrating linkage to the Duffy blood group marker have been designated CMT Type 1a. We report linkage of six CMT Type 1a families to the chromosome 17 markers EW301 (D17S58) and pA10-41 (D17S71) with maximum LOD scores of zeta = 10.49 at theta (maximum recombination fraction) = 0.05 and zeta = 7.36 at theta = 0.06, respectively.