Paucity of genes on the Drosophila X chromosome showing male-biased expression

Science. 2003 Jan 31;299(5607):697-700. doi: 10.1126/science.1079190. Epub 2003 Jan 2.


Sex chromosomes are primary determinants of sexual dimorphism in many organisms. These chromosomes are thought to arise via the divergence of an ancestral autosome pair and are almost certainly influenced by differing selection in males and females. Exploring how sex chromosomes differ from autosomes is highly amenable to genomic analysis. We examined global gene expression in Drosophila melanogaster and report a dramatic underrepresentation of X-chromosome genes showing high relative expression in males. Using comparative genomics, we find that these same X-chromosome genes are exceptionally poorly conserved in the mosquito Anopheles gambiae. These data indicate that the X chromosome is a disfavored location for genes selectively expressed in males.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Anopheles / genetics
  • Chromosome Mapping
  • Chromosomes / genetics*
  • Dosage Compensation, Genetic
  • Drosophila Proteins / genetics
  • Drosophila melanogaster / genetics*
  • Evolution, Molecular
  • Expressed Sequence Tags
  • Female
  • Gene Dosage
  • Gene Expression Profiling
  • Gene Expression*
  • Genes, Insect*
  • Genetic Linkage
  • Genomics
  • Male
  • Oligonucleotide Array Sequence Analysis
  • Ovary / metabolism
  • Ribosomal Proteins / genetics
  • Sex Characteristics
  • Testis / metabolism
  • X Chromosome / genetics*


  • Drosophila Proteins
  • Ribosomal Proteins