(AAT)n repeat in the cannabinoid receptor gene, CNR1: association with schizophrenia in a Spanish population.
The cannabinoid receptor 1 gene (CNR1) has been associated with addictive disorders and schizophrenia in different studies. We have compared the frequencies of the alleles for the 3'-UTR CNR1 microsatellite in a sample of 113 Spanish schizophrenic patients, including 68 with comorbid substance abuse, and 111 healthy controls. We report that the frequency of the allele 4 of this microsatellite is significantly lower in schizophrenia patients when compared with controls (chi(2) = 7.858; df 1; P = 0.005). No differences have been found with respect to substance abuse.Thus, the allele 4 represents, in our sample, a protective factor against schizophrenia (odds ratio 0.468, 95% confidence interval (CI) 0.27-0.79). The population attributable genetic risk for the allele 4 absence is 30% (95% CI = 17-41%) and the attributable risk for the allele 4 absence in those with schizophrenia is 53% (95% CI = 20-73%). Our results suggest that, independent of substance abuse, differences in the cannabinoid system function could be involved in the vulnerability to schizophrenia in Spanish population.
Martínez-Gras
Isabel
I
Retiro Mental Health Service, C/ Lope de Rueda n 43, 28007, Madrid, Spain. garuva@inicia.es
Hoenicka
Janet
J
Ponce
Guillermo
G
Rodríguez-Jiménez
Roberto
R
Jiménez-Arriero
Miguel Angel
MA
Pérez-Hernandez
Elena
E
Ampuero
Israel
I
Ramos-Atance
Jose Antonio
JA
Palomo
Tomas
T
Rubio
Gabriel
G
D000328:Adult; D000483:Alleles; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D008297:Male; D018895:Microsatellite Repeats / Q000235:genetics; D016017:Odds Ratio; D011569:Psychiatric Status Rating Scales; D043884:Receptor, Cannabinoid, CB1 / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012306:Risk; D012559:Schizophrenia / Q000453:epidemiology / Q000235:genetics*; D013030:Spain / Q000453:epidemiology; D018911:Trinucleotide Repeats / Q000235:genetics
D043884:Receptor, Cannabinoid, CB1