The Crouzon syndrome locus (CFD1) maps to the region of chromosome 10q2, with the tightest linkage to locus D10S205 (Z = 3.09, theta = 0.00). the Jackson-Weiss syndrome locus in the large Amish pedigree in which the condition was originally described was also linked to the chromosome 10q23-q26 region between loci D10S190 and D10S186.