Monoamine oxidase (MAO) intron 13 polymorphism and platelet MAO-B activity in combat-related posttraumatic stress disorder.
BACKGROUND
The neurobiology of posttraumatic stress disorder (PTSD) involves alterations in multiple neuroendocrine and neurotransmitter systems. Platelet monoamine oxidase (MAO-B) has been associated with susceptibility to various psychiatric disorders, personality traits and behaviors.


METHODS
Platelet MAO-B activity and MAO-B intron 13 polymorphism (a G/A substitution) were determined in male war veterans (n=106) with DSM-IV diagnosed current and chronic PTSD, divided into subgroups of PTSD patients with (n=28) or without (n=78) psychotic features, combat exposed veterans (n=41) who did not develop PTSD, and healthy control men (n=242).


RESULTS
Two-way ANOVAs revealed a significant effect of diagnosis and smoking, a significant effect of smoking, no significant effect of genotype, and no significant interaction between genotype, smoking or diagnosis, on platelet MAO-B activity. One-way ANOVAs showed significantly lower platelet MAO-B activity in smokers than in nonsmokers. After controlling for smoking, veterans with psychotic PTSD had significantly higher platelet MAO-B activity than veterans with or without PTSD, or healthy subjects.


CONCLUSIONS
The results were obtained on peripheral biochemical marker, i.e. platelet MAO activity.


CONCLUSIONS
The MAO-B intron 13 polymorphism was not functional, and did not affect platelet MAO-B activity. The allele frequencies of the MAO-B genotype were similarly distributed among healthy controls and veterans with or without PTSD and/or psychotic symptoms. The results suggest that platelet MAO-B activity, controlled for smoking status, might be used as a peripheral marker of the psychotic symptoms in PTSD.
Pivac
Nela
N
Rudjer Boskovic Institute, Division of Molecular Medicine, PO Box 180, HR-10002 Zagreb, Croatia. npivac@irb.hr
Knezevic
Jelena
J
Kozaric-Kovacic
Dragica
D
Dezeljin
Martina
M
Mustapic
Maja
M
Rak
Davor
D
Matijevic
Tanja
T
Pavelic
Jasminka
J
Muck-Seler
Dorotea
D
D000328:Adult; D001792:Blood Platelets / Q000201:enzymology*; D003130:Combat Disorders / Q000201:enzymology / Q000235:genetics*; D017523:Croatia; D005819:Genetic Markers / Q000235:genetics; D020022:Genetic Predisposition to Disease / Q000235:genetics; D005838:Genotype; D006801:Humans; D007438:Introns / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D008995:Monoamine Oxidase / Q000097:blood / Q000235:genetics*; D011110:Polymorphism, Genetic / Q000235:genetics*; D011618:Psychotic Disorders / Q000201:enzymology / Q000235:genetics; D014728:Veterans / Q000523:psychology*
D005819:Genetic Markers; D008995:Monoamine Oxidase