Genetic and physical maps of the subcentromeric region of chromosome 4. (A) Genetic map (Fan et al. 1994); (B) physical map of 4q11–q21 (The Genome Database; Stanford Human Genome Center;Karrman et al. 1997). Lack of redundancy in this YAC contig suggested the possibility of an inversion of the interval enclosed in brackets. (C) Order of loci derived from the genotyping of CEPH families. The three markers tested in this study are boxed. Markers are underlined to indicate that there were no recombinants between them. (D) Crossover map of 4q11–q21. DNA samples of seven individuals from CEPH families known to have a recombination between (D4S392/D4S2969/D4S1543) and (D4S2958/D4S2990/D4S1558/D4S3042) were genotyped for markers D4S2641, D4S1517, and D4S2403, resulting in the deduced ordering shown in C.
