CrcEP1084/CrcEP834 flies reproducibly exhibit a reduction in avoidance of the olfactory repellant 3-octanol compared to wild-type flies in an olfactory T-maze. Flies that are heteroallelic for CrcEP979/CrcEP834 have little or no odour avoidance defects. The 3-octanol avoidance of Crc10rv/CrcEP834 flies is indistinguishable from that of wild-type flies.