Abstract
In clonal unisexual vertebrates, the genes specifying the males become dispensable. To study the fate of such genes the gynogenetic all-female fish Poecilia formosa was treated with androgens. Phenotypic males were obtained that exhibited the complete set of male characteristics of closely related gonochoristic species, including body proportions, pigmentation, the extremely complex insemination apparatus of poeciliid fish, sexual behavior, and spermatogenesis. The apparent stability of such genic structures, including those involved in androgen regulation, is contrasted by high instability of noncoding sequences. Frequent mutations, their clonal transmission, and at least two truly hypervariable loci leading to individual differences between these otherwise clonal organisms were detected by DNA fingerprinting. These observations substantiate the concept that also in "ameiotic" vertebrates certain compartments of the genome are more prone to mutational alterations than others.
Full text
PDFImages in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Allendorf F. W. Protein polymorphism and the rate of loss of duplicate gene expression. Nature. 1978 Mar 2;272(5648):76–78. doi: 10.1038/272076a0. [DOI] [PubMed] [Google Scholar]
- Hubbs C. L., Hubbs L. C. APPARENT PARTHENOGENESIS IN NATURE, IN A FORM OF FISH OF HYBRID ORIGIN. Science. 1932 Dec 30;76(1983):628–630. doi: 10.1126/science.76.1983.628. [DOI] [PubMed] [Google Scholar]
- Hubbs C., Drewry G. E., Warburton B. Occurrence and Morphology of a Phenotypic Male of a Gynogenetic Fish. Science. 1959 May 1;129(3357):1227–1229. doi: 10.1126/science.129.3357.1227-a. [DOI] [PubMed] [Google Scholar]
- Parzefall J. Zur vergleichenden Ethologie verschiedener Mollienesia-Arten einschliesslich einer Höhlenform von M. sphenops. Behaviour. 1969;33(1):1–38. [PubMed] [Google Scholar]
- Rasch E. M., Monaco P. J., Balsano J. S. Cytophotometric and autoradiographic evidence for functional apomixis in a gynogenetic fish, Poecilia formosa and its related, triploid unisexuals. Histochemistry. 1982;73(4):515–533. doi: 10.1007/BF00493366. [DOI] [PubMed] [Google Scholar]
- Schartl A., Schartl M., Anders F. Promotion and regression of neoplasia by testosterone-promoted cell differentiation in Xiphophorus and Girardinus. Carcinog Compr Surv. 1982;7:427–434. [PubMed] [Google Scholar]
- Turner B. J., Elder J. F., Jr, Laughlin T. F., Davis W. P. Genetic variation in clonal vertebrates detected by simple-sequence DNA fingerprinting. Proc Natl Acad Sci U S A. 1990 Aug;87(15):5653–5657. doi: 10.1073/pnas.87.15.5653. [DOI] [PMC free article] [PubMed] [Google Scholar]