PubMed Health⌕ Search

Biomedical subjects

H Kunugi

Publications and source records attributed to H Kunugi.

At least 37 records · Page 2Linked to original sources

Cytogenetic findings in 250 schizophrenics: evidence confirming an excess of the X chromosome aneuploidies and pericentric inversion of chromosome 9.

Chromosomal abnormalities may be of help in identifying disease genes. To search for susceptibility loci for schizophrenia, we have performed chromosomal examinations by using the GTG banding technique for 250 schizophrenics. We found five cases with an aneuploidy of the X chromosome and ten cases with pericentric inversion of chromosome 9 [inv (9)]. These results confirmed an excess of the X chromosome aneuploidies in schizophrenia, indicating a possible involvement of the X chromosome in the pathogenesis of the illness. The observed incidence (4.0%) of inv (9) in our schizophrenic sample was significantly higher (p=0.013) than that reported in the general population in Japan (1.7%). Although inv (9) has been considered to be a normal variant, our observation implies a possible association between inv (9) and schizophrenia, suggesting that a susceptibility locus for the disease may be located at a breakpoint of the inversion on chromosome 9.

Adult↗

Novel polymorphism in the promoter region of the tumor necrosis factor alpha gene: No association with narcolepsy.

The striking evidence of almost 100% association of narcolepsy with human leukocyte antigens (HLA) DR2(DR15) antigen is an important clue to elucidate the molecular basis of this sleep disorder. The gene for tumor necrosis factor alpha (TNF alpha) is located in the HLA class II gene cluster. Recent studies have indicated that TNF alpha plays an important role in the regulation of normal human sleep, and regulation of this cytokine may be disturbed in narcolepsy. We searched for a mutation associated with narcolepsy in the promoter region of the TNF alpha gene by single-strand conformation polymorphism analysis. A novel polymorphism, C-850T, was found in narcoleptic patients. Genotype frequency was examined by restriction fragment length polymorphism method. No significant difference of genotype distribution was found between 92 patients with narcolepsy and 91 normal controls. These results do not support our hypothesis that genetic abnormality of TNF alpha production is pathogenetic for narcolepsy.

Alleles↗

Association between serotonin transporter gene polymorphism and anxiety-related traits.

BACKGROUND: Polymorphism in the serotonin transporter promoter gene has been recently reported to be associated with the personality trait known as anxiety-related traits. We have attempted to replicate these findings in 101 healthy Japanese subjects. METHODS: The personality traits of the subjects were assessed with the tridimensional personality questionnaire. RESULTS: An association was observed in the present study between individuals grouped according to the transporter gene and harm avoidance scores. CONCLUSIONS: These data supported that there was an association between the serotonin transporter gene and anxiety.

Adult↗

A functional polymorphism in the promoter region of monoamine oxidase-A gene and mood disorders.

A polymorphism of a variable number tandem repeat (VNTR), that was recently found in the promoter region of the monoamine oxidase-A (MAOA) gene, was shown to be associated with its transcriptional activity. This study examined whether this functional polymorphism of the MAOA gene is associated with the risk of developing mood disorders in a Japanese sample of 161 patients with bipolar disorder, 98 with unipolar depression, and 258 controls. There was no significant genotypic or allelic association, suggesting that the functional VNTR polymorphism in the MAOA gene is unlikely to play a major role in the pathogenesis of bipolar disorder or unipolar depression. Furthermore, we found no association between the polymorphism and a history of suicide attempt.

Analysis of Variance↗

Familial paroxysmal kinesigenic choreoathetosis: an electrophysiologic and genotypic analysis.

PURPOSE: We report a pedigree of familial paroxysmal kinesigenic choreoathetosis (PKC) in which five of 18 members are affected. The pathophysiologic basis for PKC is still uncertain; reflex epilepsy versus dysfunction of basal ganglia. We examined (a) whether there were ictal discharges during the attacks, and (b) a linkage between PKC and possible DNA markers linked to several familial epileptic or movement disorders. METHODS: Video-monitoring EEG was performed in two patients with PKC during attacks elicited by movements of the lower extremities. Blood samples for DNA studies were obtained from 15 members of the pedigree. Fourteen polymorphic markers on chromosomes 1p, 2q, 6p, 10q, and 20q were genotyped, and two-point lod scores were calculated for each marker under a dominant model. RESULTS: No ictal discharges were found during the attacks in both patients. We could not obtain significant linkage of PKC with any marker examined. CONCLUSIONS: The video-monitoring EEG findings in our cases strongly suggested that the etiology of PKC should be considered distinct from that of reflex epilepsy. However, the patients in this pedigree had experienced generalized convulsions in their infancies; thus we could not deny the possibility of an epileptogenic basis for PKC. There was no strong evidence for a linkage of the gene for PKC with the candidate regions on 1p, 2q, 6p, 10q, or 20q.

Athetosis↗

No changes in paired viral antibody titers during the course of acute schizophrenia.

Although there have been many studies surveying the prevalence of specific viral antibodies in a large cohort of patients with schizophrenia, changes in antibody levels during the course of acute illness have not been fully investigated. We conducted a preliminary study investigating levels of antibodies to 5 herpesviruses (herpes simplex virus type 1, cytomegalovirus, Epstein-Barr virus, varicella-zoster virus and human herpesvirus type 6) and 6 other viruses (measles, rubella, mumps, influenza A and B and Japanese encephalitis viruses) in paired sera of 8 patients with acute onset or exacerbation of schizophrenia. Assay for specific immunoglobulin M (IgM) antibody was also performed for herpesviruses and mumps. Neither any relevant change in antibody levels nor appearance of specific IgM antibody was observed for any of the viruses in any of the patients investigated. It is unlikely that the active infection or reactivation of these viruses has direct causal relationship to schizophrenia in these patients.

Acute Disease↗

No evidence for an association of polymorphisms of the tryptophan hydroxylase gene with affective disorders or attempted suicide among Japanese patients.

OBJECTIVE: Tryptophan hydroxylase is the rate-limiting enzyme in the biosynthesis of serotonin. The authors examined whether polymorphisms A218C and A779C in intron 7 of the tryptophan hydroxylase gene are associated with a risk for affective disorders or suicidal behavior. METHOD: Subjects were 141 patients with bipolar disorder and 73 patients with unipolar affective disorder, 46 of whom had a history of attempted suicide, and 208 healthy volunteers. All subjects were unrelated to each other, and all were Japanese. Genotyping was performed by polymerase chain reaction amplification followed by digestion by a restriction enzyme and single-strand conformational polymorphism analysis. RESULTS: There was no significant genotypic or allelic association of the A218C polymorphism with bipolar disorder, unipolar depression, or history of attempted suicide. In nearly 100% of the subjects, genotypes for the A779C were identical to those for the A218C. CONCLUSIONS: The authors conclude that the examined polymorphisms are unlikely to have major relevance to the pathogenesis of affective disorders or suicidal behavior.

Adult↗

The monoamine oxidase-A gene and major psychosis in Japanese subjects.

BACKGROUND: Monoamine oxidase (MAO) is a critical enzyme in deamination of biogenic amines and may be involved in the pathophysiology of major psychosis, including mood disorder and schizophrenia. Recently, evidence for genetic association between the MAO-A gene and bipolar mood disorder was obtained in Caucasians. METHODS: We investigated the polymorphisms of the MAO-A gene, which may be related to enzyme activity (T/941/G, A/1609/G), with amino-acid change (A/1609/G), in Japanese patients with bipolar disorder patients (n = 132), unipolar major depression (n = 43), or schizophrenia (n = 95), and controls (n = 169). RESULTS: No difference in the allele frequencies or genotype distribution of the T/941/G variation was observed between any disease group and the control group. As for the A/1609/G variation, no G allele was found in the Japanese subjects. CONCLUSIONS: No evidence for the genetic association between the MAO-A gene and major psychosis was obtained in the Japanese subjects.

Adult↗

Familial schizophrenia with pericentric inversion of chromosome 9: a case report.

We report a case with schizophrenia who had a pericentric inversion of chromosome 9 (inv. 9) and whose mother has the same illness and karyotype. Although inv. 9 has been considered to be a common chromosomal rearrangement without specific phenotype, recent evidence has shown that there are several different forms of inv. 9 with differential breakpoints. This indicates that phenotypes of inv. 9 may vary depending on the location of breakpoints. Thus our cases may be valuable material to localize breakpoints on chromosome 9, which may lead to cloning of a susceptibility gene for schizophrenia.

Adult↗

Association study of structural mutations of the tyrosine hydroxylase gene with schizophrenia and Parkinson's disease.

Tyrosine hydroxylase (TH) gene is the rate-limiting enzyme in the synthesis of catecholamines. Functional polymorphisms of the TH gene may be involved in the pathogenesis of neuropsychiatric diseases such as schizophrenia, affective disorders, and Parkinsonism. This study examined a possible association of two polymorphisms, both of which result in an amino acid change of the TH protein, with schizophrenia and Parkinson's disease (PD). The Val81Met polymorphism is a common variation, although its effect on the enzyme expression is unclear. Leu205Pro polymorphism is a rare mutation that is reported to cause Parkinsonism in infancy for individuals who are homozygous for the mutated type. We genotyped a Japanese sample of 194 schizophrenics, 99 patients with PD, and 161 controls for the Val81Met polymorphism by using mis-match PCR and digestion by the restriction enzyme BalI. There was no significant allelic or genotypic association of the Val81Met polymorphism with schizophrenia or PD. The Leu205Pro polymorphism was examined by using PCR and digestion by AluI; however, there was no individual who carried the mutated type of Pro205 among 50 schizophrenics or 50 patients with PD. Thus we obtained no evidence for the involvement of the two structural mutations of the TH gene in the pathogenesis of schizophrenia or PD.

Alleles↗

Possible association of missense mutation (Gly[-63]Glu) of the neurotrophin-3 gene with Alzheimer's disease in Japanese.

Several lines of evidence have suggested a possible involvement of neurotrophic factors in the pathogenesis of neurodegenerative disease. We examined whether a missense mutation (Gly[-63]Glu) of the neurotrophin-3 (NT-3) gene is associated with Alzheimer's disease (AD) in a Japanese sample of 123 patients and 215 controls. We found that homozygotes or heterozygotes for the mutated type (Glu[-63]) were significantly more common among the patients than the controls (P = 0.013, odds ratio 1.77, 95% CI 1.12-2.79). The mutated type was more frequent among the patients than the controls (P = 0.011, odds ratio 1.63, 95%CI 1.11-2.38). This association between NT-3 and AD was more prominent among those who did not carry the epsilon4 allele of the apolipoprotein E gene than those who carried the epsilon4 allele. Our results suggest that the Glu(-63) allele of the NT-3 gene by itself or another mutation nearby which would be in linkage disequilibrium to the mutation is a risk factor for AD.

Adult↗

Low activity allele of catechol-O-methyltransferase gene associated with rapid cycling bipolar disorder.

Catechol-O-methyltransferase (COMT) plays a major role in the breakdown of catecholamines. An amino acid polymorphism (val-108-met) determines high and low activity of the enzyme. A recent study in a small sample of patients with velo-cardio-facial syndrome who had bipolar affective disorder suggested that the Met (low activity) COMT allele might be associated with rapid-cycling in this population. We therefore tested the hypothesis that the Met allele might be associated with rapid cycling bipolar disorder in the wider population. We studied a sample of British Caucasian DSM-IV bipolar patients, of whom 55 met criteria for rapid cycling at some time during the illness and 110 met stringent criteria for a definite non-rapid cycling course. The COMT genotype was determined using a PCR assay. The low activity allele was more frequent in the group of rapid cyclers: 0.55 vs 0.42 (one-tailed chi 2 = 5.12, d.f. = 1, P = 0.012), and bearers of low activity alleles showed a dose-dependent increased risk of lifetime occurrence of rapid cycling: chi 2 test of linear association = 4.84, d.f. = 1, P = 0.014. Our data support the hypothesis that variation in the COMT gene modifies the course of bipolar disorder.

Alleles↗

C677T polymorphism in methylenetetrahydrofolate reductase gene and psychoses.

A common missense mutation of the methylenetetrahydrofolate reductase (MTHFR) gene (C677T) has been shown to be a risk factor for premature cardiovascular disease and neural tube defect. Deficient activity of MTHFR has also been implicated in the pathogenesis of psychiatric conditions such as schizophrenia and affective disorders. Arinami et al found an increased frequency of homozygosity for the mutated type (T677) of the MTHFR gene in schizophrenia and depression. We tried to replicate this finding in a sample of 343 patients with schizophrenia, 143 with bipolar disorder, 71 with unipolar depression, and 258 controls; however, there was no significantly increased frequency of homozygosity for the T677 allele in any of the diagnostic groups, compared to the controls. Our results suggest that homozygosity for the T677 allele of the MTHFR gene is unlikely to play a major role in the pathogenesis of schizophrenia or affective disorders in our sample.

Adult↗

No evidence for an association of affective disorders with high- or low-activity allele of catechol-o-methyltransferase gene.

Catechol-o-methyltransferase (COMT) is an enzyme that inactivates biologically active or toxic catechols. Previous studies have yielded inconsistent results on the relationship between erythrocyte COMT activity and affective disorders. Recently an amino acid change (Val-108-Met) of the COMT protein was shown to determine high- and low-activity alleles of the enzyme. Using polymerase chain reaction and the restriction enzyme NLaIII, we genotyped 107 patients with bipolar disorder, 62 with unipolar depression, and 121 controls. Neither bipolar nor unipolar patients differ significantly in the genotypic or allelic frequency from the control group. Even when the bipolar and unipolar patients were pooled into a single group, the distributions of both the genotypes and the alleles for the patient group were similar to those for the controls. We conclude that genetic variation that determines high and low activities of COMT does not have a major effect on the vulnerability to affective disorders in our sample.

Adult↗

Schizophrenia and the ciliary neurotrophic factor (CNTF) gene: no evidence for association.

The ciliary neurotrophic factor (CNTF) gene is considered a candidate gene for schizophrenia, in view of the neurodevelopmental hypothesis of the disorder. Recently, controversial results regarding an association between psychiatric disorders; mainly schizophrenia, and a null mutation of the CNTF gene were reported. We investigated this mutation in 138 Japanese patients with schizophrenia and 140 healthy control subjects. No significant difference was observed in allele frequencies or genotype distribution between the patients and control subjects. Our results did not provide evidence for the involvement of the null mutation of the CNTF gene in the development of schizophrenia.

Adult↗