FIG. 1.

Functional map of the respiratory distress critical region. (A) Summary of complementation studies showing the original respiratory distress-defining 15DttMb deletion along with the nonrescuing 1Acrg and 9ThW deletions and the rescuing 48UThc deletion. The deleted portion of each chromosome is depicted as a dashed line, and the critical functional interval is shown in grey. Deletions are shown relative to mouse chromosome 14 from 47 to 55 cM on the Mouse Genome Database genetic map. D14Mit genetic markers used for molecular mapping studies and the piebald (Ednrb) locus are positioned along the chromosome. (B) The 480-kb respiratory distress critical region, in grey, is defined by the 48UThc and 9ThW proximal deletion breakpoints. The deletions were defined by the Jax6 and Jax13 sequence-tagged site markers. The positions and sizes of the Phr1, Scel, and TC255155 transcripts based on alignments with the genomic sequence are shown below the deletion chromosomes. Arrows indicate the direction of transcription.