Inverse dosage effect of the X chromosome of Drosophila. A transgene of the white eye color gene was present in constant copy number in an autosome in a background in which the endogenous gene was deleted. When the dosage of the X chromosome was varied in one to three doses in the form of males, females and metafemales, the expression of the transgene was negatively correlated with the X dosage. Counterclockwise from the top, male, female, metafemale. See also Birchler (1992).