title: Polyploids and sex determination in Caenorhabditis elegans.
abstract: Tetraploid stocks of Caenorhabditis elegans var. Bristol carrying autosomal and X-linked markers have been produced. Tetraploid hermaphrodites fall into two categories: those that give about 1% male self-progeny and those that give 25 to 40% male self-progeny. The former are basically 4A;4X--four sets of autosomes and four sex chromosomes--and the latter are 4A;3X. Males are 4A;2X. (Diploid hermaphrodites are 2A;2X; males are 2A;1X.) Triploids were produced by crossing tetraploid hermaphrodites and diploid males. Triploids of composition 3A;3X are hermaphrodites; 3A;2X animals are fertile males. Different X-chromosome duplications were added to a 3A;2X chromosome constitution to increase the X-to-autosome ratio. Based on the resulting sexual phenotypes, we conclude that there exists on the C. elegans X chromosome at least three (and perhaps many more) dose-sensitive sites that act cumulatively in determining sex.
mesh_terms: D000818:Animals; D002107:Caenorhabditis / Q000235:genetics*; D004261:DNA Replication; D005260:Female; D005819:Genetic Markers; D009154:Mutation; D011123:Polyploidy; D012732:Sex Determination Analysis; D014960:X Chromosome
chemical_list: D005819:Genetic Markers