Lower frequency of the low activity adenosine deaminase allelic variant (ADA1*2) in schizophrenic patients.
OBJECTIVE
Adenosine may play a role in the pathophysiology of schizophrenia, since it modulates the release of several neurotransmitters such as glutamate, dopamine, serotonin and acetylcholine, decreases neuronal activity by pos-synaptic hyperpolarization and inhibits dopaminergic activity. Adenosine deaminase participates in purine metabolism by converting adenosine into inosine. The most frequent functional polymorphism of adenosine deaminase (22G→A) (ADA1*2) exhibits 20-30% lower enzymatic activity in individuals with the G/A genotype than individuals with the G/G genotype. The aim of this study was to evaluate the ADA polymorphism 22G→A (ADA1*2) in schizophrenic patients and healthy controls.


METHODS
The genotypes of the ADA 22G→A were identified with allele-specific PCR strategy in 152 schizophrenic patients and 111 healthy individuals.


RESULTS
A significant decrease in the frequency of the G/A genotype was seen in schizophrenic patients (7/152 - 4.6%) relative to controls (13/111 - 11.7%, p = 0.032, OR = 2.6).


CONCLUSIONS
These results suggest that the G/A genotype associated with low adenosine deaminase activity and, supposingly, with higher adenosine levels is less frequent among schizophrenic patients.
Dutra
Gustavo Pimentel
GP
Department of Celular and Molecular Biology, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil.
Ottoni
Gustavo L
GL
Lara
Diogo R
DR
Bogo
Maurício Reis
MR
D000243:Adenosine Deaminase / Q000235:genetics* / Q000502:physiology; D000328:Adult; D000483:Alleles; D016022:Case-Control Studies; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D008297:Male; D011110:Polymorphism, Genetic; D012559:Schizophrenia / Q000201:enzymology* / Q000503:physiopathology
D000243:Adenosine Deaminase