International Mammalian Genome Society

The 14th International Mouse Genome Conference (2000)

Table of Contents * Genes, Physical Mapping and Sequencing * Gene Identification * Bioinformatics * Common Resources * RIKEN Session * Functional Genomics * Complex Traits * Mutagenesis * Developmental Genetics and Differentiation * Verne Chapman Memorial Lecture I and II

I37. Chromosomal Localization of a Locus Responsible for Skeletal Deformities with Short Tail and Trunk of oma Mutant Mouse

Yusuke Shinkai, Yasuo Kawamoto, Tetsuo Kunieda
Graduate School of Natural Science and Technology, Okayama University, Tsushima-naka, Okayama 700-8530, Japan

Mutant mice with skeletal deformities were found in a mouse colony derived from multicross-hybrids. Posterior trunk and tail of the mutant mice are extremely shorter than those of normal mice. The mutants phenotype was controlled by a single autosomal recessive gene. We termed the locus for this mutant oma. The phenotypes resembled with those of knockout mice for Lunatic fringe (Lfng) gene and pudgy (pu) mutant mice caused by defects in Delta-like 3 (Dll3) gene. In this study, we performed linkage mapping of the oma locus as well as morphological examination of the skeleton of the mutant mice. The morphological examination showed deformities of vertebrae and fused and bifurcated ribs in adult mice and abnormal vertebrae segmentation in newborn mice. Backcross progeny obtained from cross between the oma mutant mice and JF1/Ms were typed for microsatellite markers on mouse chromosomes 5 and 7, in which Lfng and Dll3 genes are localized. The linkage analysis revealed localization of oma on the proximal region of chromosome 7 close to the Dll3 gene. These findings indicated that mutation in the Dll3 gene is likely to be responsible for the oma mutant. We are now examining the nucleotide sequence of the Dll3 gene of the mutant mouse.