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Waddle, F. 1999. Some stocks for the teaching lab.
Dros. Inf. Serv. 82: 125. View PDF
Ursprung, H. 1999. Transplanting Drosophila tissues.
Dros. Inf. Serv. 82: 125 View PDF
I use the following "unknowns" in the teaching lab: wa (sc6), we, ras2, gF, car, 1t (stw), or45a (sp2), se (h), pp (ri), red. The following stocks are used for tests with the unknowns: Ore-R, b, e, cv f, CyO/Sp bw; In(3LR)DcxF, D/Sb e.
The eye color mutations, including the garnet allele, are all easily distinguishable from wild type. Sex linked mutations were chosen such that any competent mapping test with cv and f can distinguish one locus from the others. Genes in parentheses are "teacher markers". They are mostly rank 2 or 3 mutations not obvious to the student but which allow the instructor to distinguish among stocks of similar eye color.
Each student is given one sex linked and one autosomal unknown plus the stocks to test them with. No two students have the same combination of unknowns. Depending on the autosomal unknown, either b or e is given, without identification, so that the student can do dihybrid crosses. The CyO/Sp bw; In(3LR)DcxF, D/Sb e stock is excellent for determining which chromosome an autosomal unknown is on. If the student chooses to make chromosome squashes of Ore-R heterozygotes, he/she has the opportunity to observe that one of the bands near the tip of 2R is heterozygous for a deletion.
In teaching transplantation of Drosophila imaginal discs (see Biology of Drosophila, ed., M. Demerec, New York, Wiley, 1950, pp. 350 ff, for a description of the method) one of the most frequent difficulties encountered is that the tissues get stuck in the micropipette. Siliconizing the glass capillary may overcome this problem, but a still simpler procedure is to suck a piece of larval fat body, that usually floats in the dissecting drop, into the pipette several times. This procedure coats the interior of the pipette with a thin film and effectively prevents clogging.