Positional cloning of the mod locus.
(A) Physical map showing the outcome of the linkage analysis using 792 BC1 individuals. The mod locus was narrowed to the genomic region flanked by the PCR markers M2 and Q, as indicated by the orange arrows. Putative genes predicted by the Gene model program ,  are shown below the map, and CYP15C1 (BGIBMGA011708) is shown in red. For more details refer to Figure S1. (B) A phylogenetic tree showing the relationship of CYP15C1 and other related P450 genes. The rootless tree was constructed based on the entire amino acid sequence by the neighbor-joining method using the ClustalX program . Sequences were retrieved from public databases, and the species names are abbreviated as follows: Aedes, A. aegypti; Anopheles, A. gambiae; Apis, A. mellifera; Bombyx, B. mori; Diploptera, D. punctata; Drosophila, D. melanogaster; and Tribolium, T. castaneum. The scale bar indicates the number of amino acid substitutions per site. Note that CYP15 was not found in D. melanogaster. (C) The genomic structure of CYP15C1 in the wild-type (p50T) strain. White box, grey box, and a black bar indicate untranslated, coding, and intronic regions, respectively. (D) Transcripts of CYP15C1 from p50T and mod strains. A 68-bp deletion was found in CYP15C1 of the mod strain, and this deletion introduced a premature stop codon as indicated in red. Heme-binding motifs of P450s  are indicated in orange. (E) Genomic PCR showing the presence of the 68-bp deletion in CYP15C1 from the mod strain. PCR primers (Table S1) that flank the deletion are shown by arrows in (C).