(A) A schematic diagram of the Smn gene and a portion of the Naip gene. The structure of the Smn andNaip genes was established by alignment to the homologous human genes. Note that Naip exon 5 and D13Mit37 are represented multiple times in this area but are shown only once for simplicity. (B) BAC contig of the region containing theSmn and Naip genes. Shown is the minimal number of BAC clones needed to complete a contiguous array spanning the markersD13Mit146–D13Mit37. (C) Contiguous array of YAC clones spanning the region from D13Mit36 to D13Mit70. Shown are only those YACs that were positive with two or more MIT markers mapping to this region. These YACs are negative for all other MIT markers, which suggests that they are not chimeric. The order of the markers from centromere to telomere was established by genetic and physical mapping. (D) Chromosome 13.
