An integrated deletion and physical map encompassing l71Rl, a chromosome 7locus required for peri-implantation survival in the mouse

l71Rl, a locus that maps just proximal to the pink-eyed dilution (p) locus in mouse chromosome 7, was initially identified as being required for early post-implantation survival. We define further the null phenotype of l71Rl as peri-implantation lethal, with homozygous mutant embryos degenerating be tween embryonic day 4.5 (E4.5) and E5.5. We constructed an integrated delet ion/physical map covering a 1.82-Mb chromosomal segment extending proximall y from p. This map defines the minimum critical interval for l71Rl as an 80 - to 300-kb region. This sequence-ready deletion/physical map should enable the cloning and characterization of the l71Rl gene(s). (C) 2000 Academic P ress.