Sex-ratio meiotic drive is found in diverse groups of metazoans including arthropods, mammals and plants. Drive occurs because a selfish sex chromosome, usually the X chromosome, is able to debilitate the opposite sex chromosome. The result is that males carrying the driving X chromosome produce almost all daughters. Understanding the genetics of sex-ratio meiotic drive has been hindered by the association of drive loci with large inversions. The Drosophila affinis sex-ratio system has an additional level o complexity: males lacking a Y chromosome are fertile. In fact, a male with a driving X chromosome and no Y produces mostly sons - the driving X appears to be suicidal in the absence of a Y chromosome. I propose a strategy using next generation sequencing for genomic analysis of sex-ratio meiotic drive in Drosophila affinis. Using a combination of comparative genomics of the driving and non-driving X chromosomes and transcriptomic analysis of both chromosomes in males testes, I hope to identify candidate genes involved in the drive phenotype. Subsequent analysis will help identify specific genes. The approach is novel in that I will be attempting to map genes within inversions in a non-model species, and the methods I develop will facilitate similar analysis in other systems. The biological insight obtaine from our analysis may shed light on the genetics of sex-ratio meiotic drive and sex chromosome evolution, both of which have implications for fertility.

Public Health Relevance

Drosophila melanogaster has long been used as a model for understanding a wide range of biological principles ranging from metabolism to disease to aging. Branching out to related Drosophila species allows for the exploration of equally important questions, specific to a particular species'biology. Understanding the genomics of sex-ratio meiotic drive and sex chromosome evolution may help us understand the basis of fertility problems in humans (reviewed in Burt and Trivers 2006).

Agency
National Institute of Health (NIH)
Institute
Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
Type
Postdoctoral Individual National Research Service Award (F32)
Project #
1F32HD071703-01
Application #
8254132
Study Section
Special Emphasis Panel (ZRG1-F08-E (20))
Program Officer
Taymans, Susan
Project Start
2012-03-01
Project End
2015-02-28
Budget Start
2012-03-01
Budget End
2013-02-28
Support Year
1
Fiscal Year
2012
Total Cost
$49,214
Indirect Cost
Name
Cornell University
Department
Biochemistry
Type
Schools of Arts and Sciences
DUNS #
872612445
City
Ithaca
State
NY
Country
United States
Zip Code
14850
Unckless, R L; Clark, A G (2014) Sex-ratio meiotic drive and interspecific competition. J Evol Biol 27:1513-21
Orr, H Allen; Unckless, Robert L (2014) The population genetics of evolutionary rescue. PLoS Genet 10:e1004551