Flies expressing Or35aScer\UAS.T:Hsap\MYC under the control of Scer\GAL4Or22a.8197 in a Df(2L)dp-79b/Dp(2;2)dppd21 background (called Δhalo) do not show much of a response to either 2-ethylpyrazine or 2-methylpyrazine.
When Or35aScer\UAS.T:Hsap\MYC is driven by Scer\GAL4Or22a.8197 in Df(2L)dp-79b/Dp(2;2)dppd21 (Δhalo) flies, mutant animals exhibit a strong response to exposure to pentyl acetate, ethyl butyrate, 1-hexanol, 1-octen-3-ol, E2-hexanal or 2-heptanone in the ab3A neuron. A strong response is not seen in response to exposure to ethyl acetate, methyl salicylate, 2,3-butanedione or geranyl acetate.