In this study we investigated inter-individual differences in mood response to amphetamine in relation to four polymorphisms in the FAAH gene, including the FAAH missense variant rs324420C --> A (Pro129Thr), which was previously found to be associated with street drug use and addictive traits.
The human fatty acid amide hydrolase (FAAH) missense mutation c.385 C-->A, which results in conversion of a conserved proline residue to threonine (P129T), has been associated with street drug use and problem drug abuse.
Reduced cellular expression and activity of the P129T mutant of human fatty acid amide hydrolase: evidence for a link between defects in the endocannabinoid system and problem drug use.