Knipple D C, MacIntyre R J
Mol Gen Genet. 1984;198(2):75-83. doi: 10.1007/BF00328704.
The structural gene beta-Gal-1 encoding a beta-galactosidase (EC 3.2.1.23) of Drosophila melanogaster has been mapped by two independent genetic approaches. In the first, gene dosage dependent variation in beta-galactosidase activity levels in segmental aneuploids, generated from crosses of Y-autosome translocation stocks, was determined quantitatively. A dosage sensitive region on the left arm of chromosome 2 was identified and mapped to region 26A7-9. In the second approach, two null activity variants were isolated from wild populations. It was shown by deletion analysis that these nulls map to the same region as that determined by the segmental aneuploidy method. The results of an EMS mutagenesis screen showed that, besides the beta-Gal-1 locus, there are four loci defined by recessive lethal mutations which map in the 26A7-9 region.
通过两种独立的遗传学方法对编码黑腹果蝇β-半乳糖苷酶（EC 3.2.1.23）的结构基因β-Gal-1进行了定位。第一种方法是，对由Y-常染色体易位品系杂交产生的节段非整倍体中β-半乳糖苷酶活性水平的基因剂量依赖性变异进行定量测定。在2号染色体左臂上鉴定出一个剂量敏感区域，并将其定位到26A7-9区域。在第二种方法中，从野生群体中分离出两个无活性变体。通过缺失分析表明，这些无活性变体与通过节段非整倍体方法确定的区域相同。EMS诱变筛选结果表明，除了β-Gal-1基因座外，还有四个由隐性致死突变定义的基因座位于26A7-9区域。
