Increased dopamine DRD4 receptor mRNA expression in lymphocytes of musicians and autistic individuals: bridging the music-autism connection.
BACKGROUND
People with autistic spectrum disorder (ASD) are affected by a long-life disabling condition, characterized by communication deficits, severe impairments in social functioning, and stereotyped behaviors. Although ASD individuals display several problems in interactions, it has been reported that they may show a peculiar interest in music. Previous studies have suggested a pivotal role for the dopaminergic system in the psychobiology of reward, including the pleasure of music.


METHODS
In the present study, we sought to investigate dopamine DRD3 and DRD4 receptor expression in peripheral blood lymphocytes of adult healthy musicians and age- and gender-matched patients with ASD against the background hypothesis that the dopaminergic system may contribute a biological cause to the reward dimensions of the musical experience in both healthy and autistic individuals.


RESULTS
ANOVA showed significant differences in DRD4 mRNA expression between the groups (P = 0.008). Post-hoc analysis showed significant differences between the control group and both musicians (P < 0.05) and ASD individuals (P < 0.05). No differences were found for DRD3 mRNA expression between the groups.


CONCLUSIONS
Our current results provide intriguing preliminary evidence for a possible molecular link between dopamine DRD4 receptor, music and autism, possibly via mechanisms involving the reward system and the appraisal of emotions.
Emanuele
Enzo
E
Department of Applied and Psychobehavioural Sciences, University of Pavia, Pavia, Italy. enzo.em@libero.it
Boso
Marianna
M
Cassola
Francesco
F
Broglia
Davide
D
Bonoldi
Ilaria
I
Mancini
Lara
L
Marini
Mara
M
Politi
Pierluigi
P
D000293:Adolescent; D000328:Adult; D001321:Autistic Disorder / Q000097:blood / Q000235:genetics* / Q000378:metabolism; D016022:Case-Control Studies; D004644:Emotions / Q000502:physiology; D005260:Female; D006801:Humans; D008214:Lymphocytes / Q000378:metabolism*; D008297:Male; D009146:Music; D012333:RNA, Messenger / Q000378:metabolism; D050637:Receptors, Dopamine D3 / Q000235:genetics / Q000378:metabolism; D050638:Receptors, Dopamine D4 / Q000235:genetics* / Q000378:metabolism; D012201:Reward; D015854:Up-Regulation / Q000235:genetics; D055815:Young Adult
C493593:DRD3 protein, human; C493599:DRD4 protein, human; D012333:RNA, Messenger; D050637:Receptors, Dopamine D3; D050638:Receptors, Dopamine D4