Earlier, it has been shown that genes responsible for differences in longevity between wild-type Drosophila melanogaster lines 2b and Oregon are localized in region 7A6-B2, 36E4-37B9, 37B9-D2, and 64C-65C. Quantitative complementation tests were conducted between the gene mutations localized in these regions and involved in catecholamine biosynthesis (iav (inactive), Catsup (Catecholamines up), amd (alpha methyl dopa resistant), Dox-A2 (Diphenol oxidase A2), pie (pale)) and neuron development control (Fas3 (Fascyclin 3), tup (tail up), Lim3), on the one hand, and two different normal alleles of these genes in lines 2b and Oregon, on the other. Complementation was found for genes iav, Fas3, amd and ple. The remaining genes (Catsup, Dox-A2, tup, and Lim3) are candidate genes for controlling differences in longevity between lines 2b and Oregon.