It has also been demonstrated that the level of an ionotropic N-methyl-d-aspartate 2B subunit (GRIN2B) of the glutamate receptor tends to increase after subchronic administration of clozapine, suggesting that GRIN2B may play an active role in the pathogenesis of schizophrenia and the function of clozapine medication.
We genotyped three polymorphic markers D15S1360, D15S165, and L76630 that are localized in a genomic fragment containing the CHRNA7 in 31 Azorean schizophrenia families/trios (including 41 schizophrenia individuals and 97 unaffected families members).
The result suggests that the c.-469delG and possibly other variants of the NR4A2 gene may be of relevance to the complex factors involved in the pathogenesis of schizophrenia.
The allele frequencies of the polymorphism in exon 29 of the NOS1 gene differed significantly between patients with schizophrenia and controls (chi(2) = 20.10, df = 1, P = 0.000007; relative risk = 1.92; 95% confidence interval = 1.44-2.55).
These findings suggest that the T-200G variant causes dysfunction of NMDA receptors consisting of the NR2B subunit and may be involved in the development of schizophrenia.
In this region, single-nucleotide polymorphisms within the 140-kb gene DTNBP1 (dystrobrevin-binding protein 1, or dysbindin) are strongly associated with schizophrenia.
We conclude that PDYN gene polymorphism alone does not alter the risk for schizophrenia but, by an epistatic interaction with the Gly allele of DRD3 gene, may contribute to the susceptibility to this disorder.
We also demonstrate that the behavioral phenotypes of the NRG1 hypomorphs are partially reversible with clozapine, an atypical antipsychotic drug used to treat schizophrenia.
The association of both DAAO and a new gene G72 from 13q34 with schizophrenia together with activation of DAAO activity by a G72 protein product points to the involvement of this N-methyl-d-aspartate receptor regulation pathway in schizophrenia.
This positive finding further supports the proposition that the 5-HTT-VNTR allele 12 is a risk factor for schizophrenic disorders in Chinese populations, although the effect is weak.
The association of both DAAO and a new gene G72 from 13q34 with schizophrenia together with activation of DAAO activity by a G72 protein product points to the involvement of this N-methyl-d-aspartate receptor regulation pathway in schizophrenia.
In addition, there was a significant association between the long form of DRD4 gene and schizophrenia in Caucasians, especially those with familial schizophrenia.
Because the 3'-untranslated regions of eukaryotic genes are known to regulate gene expression, the increased frequency of the Nogo CAA insert in schizophrenia may contribute to abnormal regulation of Nogo gene expression, and may indicate a role for Nogo in disturbed neurodevelopment in schizophrenia.