A deletion causing spontaneous fracture identified from a candidate region of mouse Chromosome 14
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Map-based cloning is an iterative approach that identifies the underlying genetic cause of a mutant phenotype. However, the classic protocol of positional cloning is time-consuming and labor-intensive. We now describe a genome sequence–based cloning approach that has led to localizing the underlying genetic cause of spontaneous fractures (sfx) in a mouse model. The sfx/sfx mouse is characterized by a spontaneous femoral fracture seen around 6 weeks of age, which represents a new mouse model for bone fragility. Genetic studies indicate that the phenotype of sfx/sfx mice is caused by an alteration at a single locus that is roughly mapped onto the central region of mouse Chromosome 14. Using our strategy of combining mouse genome resources and high-throughput technology, we discovered a deletion of all 12 exons in the gene for L-gulonolactone oxidase (LGO), a key enzyme in the synthesis of ascorbic acid. We have also examined the expression of LGO and found no expression of LGO in sfx mice while the LGO expresses in several tissues of normal mice. Our data demonstrated the feasibility to positionally clone the mutated gene from a non-fine-mapped locus, which has applicability to the positional cloning of genes from many other animal models, as their genome sequences are sequenced or will be sequenced soon.
KeywordsPositional Cloning Scurvy Microarray Screening Obvious Candidate Gene Positional Cloning Approach
Funding for WKG came from the Center of Excellence for Genomic and Bioinformatics, Center of Excellence for Diseases of Connective Tissues at the University of Tennessee Health Science Center, and the Veterans Administration Medical Center, Memphis, TN; and from NIH (AR51190). Funding for WGB was from NIH AR43618 and CA43619 (CORE grant, The Jackson Laboratory). Funding for YT and DG came from NIH 5U01MH61971. We thank Dr. Vicki Park for providing human DNA samples and information on polymorphism. We thank Dr. Syamal K. Bhattacharya for measuring of mineral contents of the bones.
- Ellender, G, Gazelakis, T 1996Growth and bone remodeling in a scorbutic rat modelAust Dent J4197106Google Scholar
- Gu, W, Brooks, M, Catalfamo, J, Ray, J, Ray, K 1999aTwo distinct mutations cause severe hemophilia B in two unrelated canine pedigreesThromb Haemost8212701275Google Scholar
- Gu, W, Ray, K, Pearce–Kelling, S, Baldwin, VJ, Langston, AA, et al. 1999bEvaluation of apolipoprotein H (APOH) gene as a positional candidate gene for progressive rod–cone degeneration (prcd) diseaseInvest Ophthalmol Vis Sci4012291237Google Scholar
- Gu, W, Li, XM, Roe, BA, Lau, KH, Edderkaoui, B, et al. 2003Application of genomic resources and gene expression profiles to identify genes that regulate bone densityCurr Genomics475102Google Scholar
- Guerriero, C, Santis, D, Nocini, PF, Gotte, P, Armato, U 1995Tissue culture of adult human osteoblasts isolated from jaw bonesItal J Anat Embryol 100 Suppl18393Google Scholar
- Kawai, T, Nishikimi, M, Ozawa, T, Yagi, K 1992A missense mutation of L-gulono-gamma-lactone oxidase causes the inability of scurvy-prone osteogenic disorder rats to synthesize L-ascorbic acidJ Biol Chem2672197321976Google Scholar
- Li, X, Gu, W, Masinde, G, Xu, S, Mohan, D, et al. 2001Genetic control of the rate of wound healing in miceHeredity86668674Google Scholar
- Nishikimi, M, Kawai, T, Yagi, K 1992Guinea pigs possess a highly mutated gene for L-gulono-gamma-lactone oxidase, the key enzyme for L-ascorbic acid biosynthesis missing in this speciesJ Biol Chem2672196721972Google Scholar
- Wegger, I, Palludan, B 1994Vitamin C deficiency causes hematological and skeletal abnormalities during fetal development in swineJ Nutr124241248Google Scholar