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Date Permissions Signed


Date of Award


Document Type

Masters Thesis

Degree Name

Master of Science (MS)



First Advisor

Trent, Carol, 1952-

Second Advisor

Leaf, David Scott, 1955-

Third Advisor

Schulze, Sandra R.


Sexual dimorphism is the result of a cascade of genes that triggers sex-specific development. The cascade begins with a primary signal that affects a hierarchy of genes and, through their selective activation and repression, results in the development of an individual of a particular sex. The genes in this regulatory hierarchy are very divergent, with little conservation across taxa. However, homologs of doublesex, a master regulator in the sexdetermining cascade of Drosophila melanogaster, have been found in organisms ranging from nematodes to humans. These homologs are identified by the DM domain, a DNAbinding motif found in genes that function as transcription factors. The DM domain defines an entire family of genes, of which only a select few play a role in sex determination. Here I describe a family of four DM-containing genes in the parasitoid wasp Nasonia vitripennis. Using molecular and computational techniques, I completed the sequence of two previously discovered members of this family and identified two new genes that contain the DM domain. One of these new genes, NvDM4, shows sex-specific expression reminiscent of the doublesex gene, suggesting that it is part of the sex-determination cascade in N. vitripennis.





Western Washington University

OCLC Number


Subject – LCSH

Drosophila melanogaster--Genetics; Parasitic wasps--Genetics; Sex determination, Genetic




masters theses




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