de Carvalho A B, Klaczko L B
Departamento de Genética, Universidade Federal do Rio de Janeiro, Brazil.
Heredity (Edinb). 1994 Dec;73 ( Pt 6):573-9. doi: 10.1038/hdy.1994.164.
X-linked meiotic drive causing female-biased progenies is known to occur in nine Drosophila species and is called 'sex-ratio'. In D. mediopunctata this trait is associated with the X:21 chromosome inversion and has variable expression. We describe here a powerful Y-linked suppressor system of sex-ratio expression in this species. There are two types of Y chromosomes (suppressor and nonsuppressor) and two types of X:21 chromosomes (suppressible and unsuppressible). Sex-ratio expression is suppressed in males with the 21suppressible/Ysuppressor genotype, whereas the remaining three genotypes produce female-biased progenies.
已知在九种果蝇中会出现导致雌性后代偏多的X连锁减数分裂驱动力，这种现象被称为“性比”。在中斑果蝇中，这一性状与X:21染色体倒位相关，并且具有可变表达。我们在此描述了该物种中一种强大的抑制性比表达的Y连锁系统。存在两种类型的Y染色体（抑制型和非抑制型）以及两种类型的X:21染色体（可抑制型和不可抑制型）。具有21可抑制型/Y抑制型基因型的雄性个体的性比表达受到抑制，而其余三种基因型则产生雌性偏多的后代。
