Association of promoter variants of human dopamine transporter gene with schizophrenia in Han Chinese.

Objective: Although dopamine was implicated in the etiology of schizophrenia, the human dopamine transporter gene (DAT1; SLC6A3) has not consistently been associated with schizophrenia. The purpose of this study was to examine whether six polymorphisms within the DAT1 gene are associated with schizophrenia.

Methods: Six polymorphisms of the DAT1 gene (3 SNPs [rs6413429, rs2652511, and rs2975226] in the promoter region, one SNP [rs6347] in exon 9, and one SNP [rs27072]/one variable number tandem repeat [VNTR] in exon 15) were analyzed in 352 Chinese patients with schizophrenia and in 311 healthy controls.

Brain-derived neurotrophic factor Val66Met polymorphism: association with psychopathological symptoms of schizophrenia?

Brain-derived neurotrophic factor (BDNF) has been proposed as a risk factor for schizophrenia, but no consistent association between BDNF Val66Met polymorphism and schizophrenia has been established. Therefore, analyses with larger sample sizes and better methodology are needed. To examine whether BDNF Val66Met polymorphism is associated with schizophrenia, schizophrenia patients (n=251) and healthy volunteers (n=284) were recruited for a case-control analysis.

Neither single-marker nor haplotype analyses support an association between monoamine oxidase A gene and bipolar disorder.

Monoamine oxidase A (MAOA) abnormality has been suggested as a crucial factor in the pathogenesis of mood disorder, because MAOA is associated with the metabolism of monoamines such as serotonin and norepinephrine. Various MAOA gene polymorphisms have been investigated for possible associations with bipolar disorder (BD), but the results are controversial. Our goal was to investigate whether MAOA gene polymorphisms, especially the promoter uVNTR polymorphism and the EcoRV polymorphism, are associated either with BD or with different clinical subtypes of BD.

Association of monoamine oxidase A (MAOA) polymorphisms and clinical subgroups of major depressive disorders in the Han Chinese population.

It has been proposed that an MAOA abnormality may be an important factor in the development of major depressive disorder (MDD). Various polymorphisms of the MAOA gene have been investigated for possible associations with mood disorders, but results have been inconsistent. The goal of the present study was to investigate whether polymorphisms of the MAOA gene are associated with MDD or alternatively with different clinical subgroups of MDD.

Lack of association between dopamine D3 receptor Ser9Gly polymorphism and schizophrenia in Han Chinese population.

Background: The Ser9Gly polymorphism in dopamine D3 receptor gene (DRD3) was considered an important factor in the pathogenesis of schizophrenia. Allele and genotype frequencies of this polymorphism were studied in different ethnic groups of schizophrenic patients. However, the results have been inconclusive.

Norepinephrine transporter polymorphisms T-182C and G1287A are not associated with alcohol dependence and its clinical subgroups.

Several studies have suggested that the norepinephrine transporter (NET) may play an important role in the pathogenesis of alcohol dependence. Additional studies have shown that the polymorphisms of T-182C (rs2242446) and G1287A (rs5569) in NET gene (hSLC6A2) may affect the NET function. Therefore, in this study, we examined whether these hSLC6A2 gene polymorphisms are a susceptibility factor for alcohol dependence or its clinical subgroup(s).