Association study of the 5-HT6 receptor gene in schizophrenia

Abstract

Serotonergic (5-hydroxytryptamine; 5-HT) transmission may play an important role in the treatment and/or pathogenesis of schizophrenia. Previous studies reported that several atypical antipsychotic agents have high affinities for the 5-HT6 receptor. The 5-HT6 receptor gene polymorphism might contribute to the genetic background of this disorder. One hundred and fifty unrelated patients with schizophrenia and 150 unrelated healthy controls were genotyped for a biallelic polymorphism (267C/T) at the 5-HT6 receptor gene. No significant positive association between the 5-HT6 receptor genotype and schizophrenia was observed. Our results suggests that the 267C/T polymorphism of the 5-HT6 receptor gene may not be involved in the susceptibility to schizophrenia.

Lack of an association between 5‐HT6 receptor gene polymorphisms and suicide victims

“…In this study, no association was found between the (GCC) 2/3 polymorphism and suicide victims. In the 267C/T and (GCC) 2/3 polymorphisms, the genotype and allele distributions in this study were almost consistent with those previously reported by Shinkai et al 28 . and Ohmori et al ., 24 respectively.…”

“…Positive associations were found between the 267T allele and schizophrenia, 29 and between the 267C allele and bipolar affective disorder, 25 but other studies 28,30 did not find an association between the 5‐HT 6 receptor gene and either schizophrenia or affective disorder. Thus, the results are still greatly inconclusive about the association of 5‐HT 6 receptor gene with specific psychiatric disorders.…”

Increased impulsivity and disrupted attention induced by repeated phencyclidine are not attenuated by chronic quetiapine treatment

“…Clozapine exhibits significant 5-HT 6 receptor antagonism, while quetiapine does not interact significantly with this receptor. Some studies have found altered 5-HT 6 mRNA expression in schizophrenia patients (East et al, 2002), and a 5-HT 6 polymorphism has been reported to be a risk factor for schizophrenia (Tsai et al, 1999; but see Shinkai et al, 1999; Ohmori et al, 2001) and to affect the therapeutic response to clozapine treatment (Yu et al, 1999; Huezo-Diaz et al, 2001). Selective 5-HT 6 receptor antagonists have been found to improve performance in a range of cognitive tasks in adult (Rogers and Hagan, 2001; Woolley et al, 2001; Hatcher et al, 2002; Hirst et al, 2003; King et al, 2004; but see Lindner et al, 2003) and aged rats (Foley et al, 2004; Kwon et al, 2004; Hirst et al, 2006), and attenuate memory impairment induced by anticholinergic drugs (Meneses, 2001; Szczepanski et al, 2002; Hirst et al, 2003, 2006; Woolley et al, 2003).…”

Serotonin 6 receptor gene and schizophrenia: case‐control study and meta‐analysis

“…Tsai et al (1999) reported that HTR6 was associated with schizophrenia in the Chinese population. However, the remaining studies showed no association (Shinkai et al, 1999;Vogt et al, 2000;Chiu et al, 2001). To overcome the limitation of heterogeneous results in the dominant model, a replication study using larger samples or samples of other populations will be required.…”

“…Tsai et al (1999) reported that HTR6 was associated with schizophrenia in the Chinese population. However, other studies, including two studies using Japanese samples, showed no association (Shinkai et al, 1999;Vogt et al, 2000;Chiu et al, 2001;Ohmori et al, 2002). Prior association studies using the "candidate gene approach" had the serious problem of having included relatively small samples, including only between 46-186 schizophrenia patients and 46-163 controls.…”