PHYSICAL LOCALIZATION OF EED - A REGION OF MOUSE CHROMOSOME-7 REQUIRED FOR GASTRULATION

In the mouse, the embryonic ectoderm development (eed) region is defin ed by deletions encompassing the albino (c) locus of chromosome 7. The region is located 1-2 cM distal to the c locus and was of undetermine d size. Embryos homozygous for deletions removing eed display defects in axial organization during gastrulation. Two loci, identified by che mical mutagenesis, are known to map within the eed interval. One, l7Rn 5, probably represents the gene required for gastrulation. The second, l7Rn6, is required for survival after birth. fit1, a third locus iden tified by chemical mutagenesis, maps distal to the eed interval and is also required for survival after birth. A 900-kb YAC contig has been constructed, and deletion breakpoints defining the limits of the regio ns containing these loci have been localized, Their positions place th e eed region within a maximum 150-kb interval at the proximal end of t he contig, while fit1 maps to a 360-kb interval within the middle of t he contig. Several clusters of rare-cutting restriction sites map with in these regions and represent potential locations of candidate genes. (C) 1995 Academic Press, Inc.