RT Journal Article SR Electronic T1 Sex Determination in the Social Amoeba Dictyostelium discoideum JF Science JO Science FD American Association for the Advancement of Science SP 1533 OP 1536 DO 10.1126/science.1197423 VO 330 IS 6010 A1 Bloomfield, Gareth A1 Skelton, Jason A1 Ivens, Alasdair A1 Tanaka, Yoshimasa A1 Kay, Robert R. YR 2010 UL http://science.sciencemag.org/content/330/6010/1533.abstract AB The genetics of sex determination remain mysterious in many organisms, including some that are otherwise well studied. Here we report the discovery and analysis of the mating-type locus of the model organism Dictyostelium discoideum. Three forms of a single genetic locus specify this species' three mating types: two versions of the locus are entirely different in sequence, and the third resembles a composite of the other two. Single, unrelated genes are sufficient to determine two of the mating types, whereas homologs of both these genes are required in the composite type. The key genes encode polypeptides that possess no recognizable similarity to established protein families. Sex determination in the social amoebae thus appears to use regulators that are unrelated to any others currently known.