Sixty‐two patients with schizophrenia and 96 normal controls were investigated for genetic association with restriction fragment length polymorphisms (RFLPs) in the serotonin receptor genes. A positive association between the serotonin 2A receptor gene (HTR2A) and schizophrenia was found, but not between schizophrenia and the serotonin 1A receptor gene. The positive association we report here would suggest that the DNA region with susceptibility to schizophrenia lies in the HTR2A on the long arm of chromosome 13. © 1996 Wiley‐Liss, Inc.

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The hyperactivity of dopaminergic systems is one of the major etiological hypotheses of schizophrenia. The major support for this hypothesis is that effective antipsychotic drugs bind to dopamine receptors and improve acute schizophrenic symptoms. For this reason, we investigated the allelic association between schizophrenia and polymorphisms of the DRD2 genes for the Ser/Cys311 and -141C Ins/Del. The subjects were 190 schizophrenics (120 males and 70 females) and 103 normal controls (53 males and 50 females). There were no significant differences between the patients and controls in the allele frequencies and the frequencies of the genotypes. We found no statistical association between schizophrenia and polymorphisms of the DRD2 genes for the Ser/Cys311 and -141C Ins/Del. These results indicate that the DRD2 gene may not develop schizophrenia. Next, we examined whether the genotypes influence the symptoms of schizophrenia the using Positive and Negative Symptom Scale scores. The Ser/Cys patients exhibited significantly lower positive and negative symptom scores than Ser/Ser patients. Patients with Del/Del, Ins/Del, or Ins/Ins showed higher positive symptom scores in descending order. This result suggested that the Del allele worsens the positive symptoms. We concluded that the DRD2 receptor gene may not influence the onset of schizophrenia, but there is a strong possibility that the Cys311 and -141C Del have a significant influence on the symptoms of schizophrenia.

We examined the allelic association between the dopamine D2 receptor (DRD2) gene and alcoholism in 100 biologically unrelated Japanese alcoholics and 93 unrelated controls. Genomic DNA was prepared from peripheral white blood cells using the phenol-chloroform method. A 310-bp region surrounding the TaqA site at the DRD2 locus was amplified by polymerase chain reaction (PCR), and the PCR product was incubated with TaqI. The A1 allele remained intact while the A2 allele was cut. The frequency of the A1/A1 genotype and the frequency of the A1 allele were higher in early-onset alcoholics than in controls, P < 0.05 and P < 0.01, respectively. Moreover, the frequency of the A1/A1 genotype and the frequency of the A1 allele were higher in early-onset alcoholics with family histories of alcohol dependence than in controls, P < 0.01 and P < 0.01, respectively. The results indicate that the DRD2 gene is associated with susceptibility to early-onset alcoholism, and that each additional A1 allele shifts onset of alcoholism to an earlier age.

BackgroundIn Japan, cognitive behavioral therapy (CBT) for panic disorder (PD) is not well established. Therefore, a feasibility study of the clinical effectiveness and cost-effectiveness of CBT for PD in a Japanese clinical setting is urgently required. This was a pilot uncontrolled trial and the intervention consisted of a 16-week CBT program. The primary outcome was Panic Disorder Severity Scale (PDSS) scores. Quality of life was assessed using the EuroQol’s EQ-5D questionnaire. Assessments were conducted at baseline, 8 weeks, and at the end of the study. Fifteen subjects completed outcome measures at all assessment points.ResultsAt post-CBT, the mean reduction in PDSS scores from baseline was −6.6 (95 % CI 3.80 to −9.40, p < 0.001) with a Cohen’s d = 1.77 (95 % CI 0.88–2.55). Ten (66.7 %) participants achieved a 40 % or greater reduction in PDSS. By calculating areas under the curve for EQ-5D index changes, we estimated that patients gained a minimum of 0.102 QALYs per 1 year due to the CBT.ConclusionsThis study demonstrated that individual CBT for PD may be useful in Japanese clinical settings but further randomized control trials are needed. Trial registration: UMIN-CTR UMIN000022693 (retrospectively registered)