The latest collection of articles inJournal of Biologyis now available to view free of charge on theJournal of Biologywebsite. In this recent research article, Arthur Arnold and colleagues show that there is an overdose of sex-linked genes in birds. The male:female ratios of gene expression in zebra finch and chicken reveal that birds, unlike mammals, have surprisingly ineffective sex-chromosome dosage compensation mechanisms resulting in an imbalance between autosomal and sex-linked genes.

		Research article Dosage compensation is less effective in birds than in mammals Yuichiro Itoh, Esther Melamed, Aldons J Lusis, Arthur P Arnold and colleagues Journal of Biology2007,6:2 (22 March 2007) [Abstract] [Full text] [PDF]
		Minireview Does gene dosage really matter? Jennifer A Marshall Graves and Christine M Disteche Journal of Biology2007,6:1 (22 March 2007) [Abstract] [Full text] [PDF]