Amnesiac gene

The amnesiac (amn) gene in Drosophila is a mutant suppressor of the dunce gene. The gene produces a neuropeptide^[1][2][3] of the same name.^[4]

By suppressing dunce through mutagenesis, the amnesiac gene plays a role in reproduction of Drosophila because dunce is the sterility gene.^[3][5] This molecule has similar peptides to pituitary adenylyl cyclase-activating peptide (PACAP) and growth hormone-releasing hormone (GHRH).^[2][3] The biological role of amnesiac gene is activating the adenyl cyclase second messenger pathway (cAMP) involved in its memory retrieval through these two peptides.^[1][2][5][6] The sensory and motor capabilities of amnesiac are normal, but it is memory retrieval that is affected, not storage.^[7] The amnesiac gene is directly involved in development of memory retrieval in the brain along with alcohol sensitivity patterning.^[1][6]

Defects associated with amnesiac gene include: increased sensitivity to alcohol,^[6] normal initial memory, and failure for adult memory formation.^[5] Defects associated with amnesiac are due to the behavior of amn as a sex-linked recessive on the X chromosome.^[7] An abnormality on one allele of the genetic mutant, amnesiac, that increases sensitivity to alcohol is called cheapdate.^[2][6] Scientists have not generated a knockout model yet for the amnesiac gene due to the mutant effects created on multiple genes along with the need for further research studies about the amnesiac gene.