Send to

Choose Destination
Science. 2017 May 12;356(6338):642-645. doi: 10.1126/science.aam5498.

Male sex in houseflies is determined by Mdmd, a paralog of the generic splice factor gene CWC22.

Author information

Groningen Institute for Evolutionary Life Sciences, University of Groningen, Post Office Box 11103, 9700 CC, Groningen, Netherlands.
Institute of Molecular Life Sciences, University of Zurich, CH-8057 Zurich, Switzerland.
Department of Developmental Biology, Johann-Friedrich-Blumenbach Institute of Zoology and Anthropology, Göttingen Center of Molecular Biosciences, University of Goettingen, Göttingen, Germany.
SIB Swiss Institute of Bioinformatics, University of Zurich, Zurich, Switzerland.
Institute of Molecular Life Sciences, University of Zurich, CH-8057 Zurich, Switzerland.


Across species, animals have diverse sex determination pathways, each consisting of a hierarchical cascade of genes and its associated regulatory mechanism. Houseflies have a distinctive polymorphic sex determination system in which a dominant male determiner, the M-factor, can reside on any of the chromosomes. We identified a gene, Musca domesticamale determiner (Mdmd), as the M-factor. Mdmd originated from a duplication of the spliceosomal factor gene CWC22 (nucampholin). Targeted Mdmd disruption results in complete sex reversal to fertile females because of a shift from male to female expression of the downstream genes transformer and doublesex The presence of Mdmd on different chromosomes indicates that Mdmd translocated to different genomic sites. Thus, an instructive signal in sex determination can arise by duplication and neofunctionalization of an essential splicing regulator.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for HighWire
Loading ...
Support Center