The histone acetyltransferase MOF (males-absent-on-the-first) is required for the regulation of X chromosome gene dosage compensation in Drosophila males. In this issue, Kind et al. (2008) show that MOF is also found on autosomes and that it has two modes of binding: one in males for X chromosome dosage compensation and the other in both sexes for X chromosome and autosomal gene regulation inde...

Deletions, commonly referred to as deficiencies by Drosophila geneticists, are valuable tools for mapping genes and for genetic pathway discovery via dose-dependent suppressor and enhancer screens. More recently, it has become clear that deviations from normal gene dosage are associated with multiple disorders in a range of species including humans. While we are beginning to understand some of ...

Mammalian X and Y Chromosomes evolved from an ordinary autosomal pair. Genetic decay of the Y led to X Chromosome inactivation (XCI) in females, but some Y-linked genes were retained during the course of sex chromosome evolution, and many X-linked genes did not become subject to XCI. We reconstructed gene-by-gene dosage sensitivities on the ancestral autosomes through phylogenetic analysis of m...

Previous studies on gene expression in aneuploids revealed numerous trans-acting dosage effects. Segmental aneuploidy of each varied chromosomal region exhibited predominantly inverse effects on several target genes. Here, dosage regulation was examined in a maize (Zea mays L.) ploidy series where the complete genomic complement is varied. Total RNA from leaf tissue of monoploid, diploid, tripl...

The gene dosage balance hypothesis states that a concentration imbalance among components of macromolecules is often deleterious. Thus this notion potentially provides a mechanistic explanation for understanding genetic dominance and gene duplicability. Accumulating evidence emerged from recent genomic data has strongly supported this hypothesis. Further efforts are needed to understand dosage ...

Gene-dosage responses for a group of six wheat endosperm proteins have been investigated by using compensated nulli-tetrasomic lines of cv. Chinese Spring. Practically linear dosage responses have been observed for all the proteins. However, for two of the proteins (and probably for a third one), the net output of protein, at each dosage of its structural gene, was 30-80% higher when the chromo...