Simpler mode of inheritance of transcriptional variation in male Drosophila melanogaster

Authors

Marta Wayne, University of Florida, Gainesville, FLFollow
Marina Telonis-Scott, University of Florida, Gainesville, FL
Lisa Bono, Ohio UniversityFollow
Lawrence G. Harshman, University of Nebraska - LincolnFollow
Artyom Kopp, University of California, DavisFollow
Sergey V. Nuzhdin, University of Southern California, Los AngelesFollow
Lauren McIntyre, University of Florida, Gainesville, FLFollow

Date of this Version

11-20-2007

Document Type

Article

Citation

PNAS, November 20, 2007, vol. 104, no. 47, pp. 18577–18582

doi: 10.1073/pnas.0705441104

Comments

© 2007 by The National Academy of Sciences of the USA. Used by permission.

Abstract

Sexual selection drives faster evolution in males. The X chromosome is potentially an important target for sexual selection, because hemizygosity in males permits accumulation of alleles, causing tradeoffs in fitness between sexes. Hemizygosity of the X could cause fundamentally different modes of inheritance between the sexes, with more additive variation in males and more nonadditive variation in females. Indeed, we find that genetic variation for the transcriptome is primarily additive in males but nonadditive in females. As expected, these differences are more pronounced on the X chromosome than the autosomes, but autosomal loci are also affected, possibly because of X-linked transcription factors. These differences may be of evolutionary significance because additive variation responds quickly to selection, whereas nonadditive genetic variation does not. Thus, hemizygosity of the X may underlie much of the faster male evolution of the transcriptome and potentially other phenotypes. Consistent with this prediction, genes that are additive in males and nonadditive in females are overrepresented among genes responding to selection for increased mating speed.

Supplementary material is attached below.