King T R
Laboratory of Genetics, University of Wisconsin-Madison 53706.
Genet Res. 1991 Feb;57(1):55-9. doi: 10.1017/s0016672300029049.
To evaluate whether sex reversal contributes to sex-ratio imbalance among t6/tw5 double heterozygotes, the cross performed by K. B. Bechtol (Genetical Research 39, 1982, 79-84), T/t6 x T/tw5, was repeated. Significantly more normal-tailed (t6/tw5) females than males were recovered. By contrast, sex ratios were normal among tailless progeny resulting from this cross and among all classes produced by control crosses. Hybridization of a Y-specific DNA probe with genomic DNA from phenotypic females revealed no XY, sex-reversed males. On the genetic backgrounds that generated only moderate transmission distortion of tw5 (81-85%), the overall viability of the doubly heterozygous progeny was only 50% and the sex-ratio skew among this class was strong. However, on a genetic background that displayed extreme tw5 transmission (99%), embryonic viability was more than 80% and the sex-ratio imbalance was weak.
为了评估性反转是否导致t6/tw5双杂合子的性别比例失衡，重复了K. B. 贝克托尔（《遗传研究》39卷，1982年，第79 - 84页）所做的杂交实验，即T/t6 × T/tw5。回收的正常尾（t6/tw5）雌性显著多于雄性。相比之下，该杂交产生的无尾后代以及对照杂交产生的所有类别中的性别比例均正常。用Y特异性DNA探针与表型雌性的基因组DNA杂交，未发现XY型性反转雄性。在仅产生中等程度tw5传递扭曲（81 - 85%）的遗传背景下，双杂合后代的总体活力仅为50%，且该类别中的性别比例偏差较大。然而，在显示极端tw5传递（99%）的遗传背景下，胚胎活力超过80%，性别比例失衡较弱。
