HOW GENES AFFECT MEMORY
Long-term memories are less likely to be formed if certain genes are not activated, which is why it's at the genetic level that scientists are trying to effect change. Normally, inside cell nuclei, DNA tightly wraps around a protein spool, called a histone. A small molecule called an acetyl group attaches to a particular histone known as H4. When this happens, the DNA wrapped around the spool loosens slightly. The loosening of the DNA makes it more available for the biological process, called transcription, that permits the gene to be expressed into neurotransmitters.