Analysis of monoamine oxidase A (MAO-A) promoter polymorphism in male heroin-dependent subjects: behavioural and personality correlates.
The promoter of the monoamine oxidase A (MAO-A) gene was analysed to test whether length variation of the repeat polymorphism contributes to variation in individual vulnerability to aggressive-criminal behaviour, and liability to heroin dependence. The repeat number of the MAO-A polymorphism was assessed in 199 male subjects of Italian descent, a sample comprising 95 healthy subjects and 104 heroin-dependent subjects including 52 addicted individuals with violent behaviour and antisocial personality disorder. The frequency of the low-activity 3-repeat allele was significantly higher in violent offenders among heroin addicts, compared to addicted individuals without antisocial behaviour (34.6 vs. 15.4%; p<0.03) and controls (18.9%; p<0.05). No significant difference was evidenced in the frequencies of the MAO-A alleles between heroin-dependent subjects in general and control subjects. High activity 4-repeat allele frequency was significantly higher in addicted individuals without antisocial behavior compared to antisocial-aggressive heroin-dependent subjects (76.9 vs. 55.8%; p<0.02). Buss Durkee Hostility Inventory (BDHI) mean total scores were significantly higher in heroin addicts than in controls (p<0.001), and in antisocial-violent heroin addicts in comparison with addicted individuals without antisocial behaviour (p<0.005). Among heroin addicts BDHI irritability, suspiciousness and resentment subscales scores were found significantly higher in low activity 3-repeat allele subjects than in high activity alleles subjects (p<0.001; p<0.05; p<0.05, respectively). No association was found between MAO-A polymorphism and suicide history. Our findings suggest that the low-activity 3-repeat allele of the MAO-A promoter polymorphism confers increased susceptibility to antisocial-violent behavior and aggressiveness, rather than drug dependence per se, in heroin-dependent males.
Gerra
G
G
Centro Studi Farmaco-tossicodipendenze, Ser T, AUSL, Italy. g.gerra@palazzochigi.it
Garofano
L
L
Bosari
S
S
Pellegrini
C
C
Zaimovic
A
A
Moi
G
G
Bussandri
M
M
Moi
A
A
Brambilla
F
F
Mameli
A
A
Pizzamiglio
M
M
Donnini
C
C
D000328:Adult; D000374:Aggression / Q000502:physiology; D000987:Antisocial Personality Disorder / Q000235:genetics*; D003617:Dangerous Behavior; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D006556:Heroin Dependence / Q000201:enzymology / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008995:Monoamine Oxidase / Q000235:genetics*; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D011401:Promoter Regions, Genetic
D008995:Monoamine Oxidase