Figure 1.

Chromosomal and genetic locations of microsatellite markers. The deCODE sex-equal genetic map of human chromosome 21 (male length 47.31cM, female length 76.40 cM, sex-equal length 61.86 cM¹⁴) is shown on the right, and microsatellite marker positions are extrapolated to their locations on the cytogenetic map in the center by solid or dashed lines. Only the microsatellite markers used in this study, spanning the entire long arm, are named: these and the remaining deCODE markers are represented by hashes along the length of the genetic map, and they are connected to the cytogenetic map by solid lines; two additional markers were genotyped and their positions, interpolated on the genetic map (based on the chromosome 21 DNA sequence), are represented by diamonds and connected to the cytogenetic map by dashed lines. Nine genes that are differentially expressed in mice with an HSCR phenotype⁹ are shown on the cytogenetic map (red text and lines)^14,15.