Double Anal Fin (Da): A Medaka Mutant Exhibiting a Mirror-Image Pattern Duplication of the Dorsal–Ventral Axis
A medaka Double anal fin (Da) mutant, spontaneously isolated from the wild-type, exhibits a unique ventralizing phenotype consisting of a mirror-image duplication across the lateral midline in the dorsal trunk-tail region. No similar mutation has been reported in other model organisms. Hence, the Da mutant provides a unique model system for investigation of the mechanisms controlling the overall dorsal–ventral patterning of the vertebrate trunk-tail region. In this chapter, we introduce (1) a brief history of the Da mutant; (2) details of the morphological phenotype of Da; (3) positional cloning of the Da mutation; (4) the Da mutant in relation to fish evolution; and (5) Da as a potential model for human disease.
KeywordsBacterial Artificial Chromosome Bacterial Artificial Chromosome Clone Spina Bifida Neural Spine Spina Bifida Occulta
- Hammerschmidt M, Pelegri F, Mullins MC et al (1996) dino and mercedes, two genes regulating dorsal development in the zebrafish embryo. Development (Camb) 123:95–102Google Scholar
- Ledent V (2002) Postembryonic development of the posterior lateral line in zebrafish. Development (Camb) 129:597–604Google Scholar
- Tomita H (1975) Mutant genes in the medaka. In: Yamamoto T (ed) Medaka (killifish) biology and strains. Keigaku, TokyoGoogle Scholar