Departmento de Biologia, Universidade de São Paulo, C. P. 11461, São Paulo, 05421, Brazil.
Genetics. 1980 Mar;94(3):663-73. doi: 10.1093/genetics/94.3.663.
It was previously assumed that the X-linked recessive mutation, sepia, induced errors in X-chromosome elimination during early embryogenesis of Sciara ocellaris. The results obtained in the present analysis corroborate this assumption and permit a further classification of the type of error this mutation induces. Among 85,244 individuals analyzed, three kinds of aberrant flies were identified: mosaics (0.01%), gynandromorphs (0.42%) and phenotypically exceptional individuals (0.25%). The origin of these abnormal flies could be ascribed to errors in selective elimination of X chromosomes that occur in male meiosis or during the early cleavages of the zygote nuclei. This last kind of error could be classified into three types: (a) error in number, (b) error in type, and (c) error in number and type of X chromosome eliminated. Evidence is provided indicating that sepia has no direct effect on the X chromosome; it has a maternal influence and exerts its effect only in the heterozygous condition.
先前人们认为，X 连锁隐性突变 sepia 在 Sciara ocellaris 的早期胚胎发生过程中诱导了 X 染色体消除的错误。本分析得到的结果证实了这一假设，并允许对该突变诱导的错误类型进行进一步分类。在分析的 85244 个人中，鉴定出了三种异常蝇：嵌合体（0.01%）、雌雄嵌合体（0.42%）和表型异常个体（0.25%）。这些异常蝇的起源可以归因于雄性减数分裂或合子核早期分裂过程中 X 染色体选择性消除的错误。这种最后的错误可以分为三种类型：（a）数量错误，（b）类型错误，和（c）消除的 X 染色体的数量和类型错误。有证据表明 sepia 对 X 染色体没有直接影响；它具有母性影响，仅在杂合状态下发挥作用。
