RESUMEN
BACKGROUND: Despite the extensive literature assessing associations between religiosity/spirituality and health, few studies have investigated the clinical applicability of this evidence. The purpose of this paper was to assess the impact of religious/spiritual interventions (RSI) through randomized clinical trials (RCTs). METHOD: A systematic review was performed in the following databases: PubMed, Scopus, Web of Science, PsycINFO, Cochrane Collaboration, Embase and SciELO. Through the use of a Boolean expression, articles were included if they: (i) investigated mental health outcomes; (ii) had a design consistent with RCTs. We excluded protocols involving intercessory prayer or distance healing. The study was conducted in two phases by reading: (1) title and abstracts; (2) full papers and assessing their methodological quality. Then, a meta-analysis was carried out. RESULTS: Through this method, 4751 papers were obtained, of which 23 remained included. The meta-analysis showed significant effects of RSI on anxiety general symptoms (p < 0.001) and in subgroups: meditation (p < 0.001); psychotherapy (p = 0.02); 1 month of follow-up (p < 0.001); and comparison groups with interventions (p < 0.001). Two significant differences were found in depressive symptoms: between 1 and 6 months and comparison groups with interventions (p = 0.05). In general, studies have shown that RSI decreased stress, alcoholism and depression. CONCLUSIONS: RCTs on RSI showed additional benefits including reduction of clinical symptoms (mainly anxiety). The diversity of protocols and outcomes associated with a lack of standardization of interventions point to the need for further studies evaluating the use of religiosity/spirituality as a complementary treatment in health care.
Asunto(s)
Ansiedad/terapia , Depresión/terapia , Meditación , Salud Mental/normas , Cuidado Pastoral , Psicoterapia/métodos , Humanos , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
Chronotype or diurnal preference is a questionnaire-based measure influenced both by circadian period and by the sleep homeostat. In order to further characterize the biological determinants of these measures, we used a hypothesis-free approach to investigate the association between the score of the morningness-eveningness questionnaire (MEQ) and the Munich chronotype questionnaire (MCTQ), as continuous variables, and volumetric measures of brain regions acquired by magnetic resonance imaging (MRI). Data were collected from the Baependi Heart Study cohort, based in a rural town in South-Eastern Brazil. MEQ and anatomical 1.5-T MRI scan data were available from 410 individuals, and MCTQ scores were available from a subset of 198 of them. The average MEQ (62.2 ± 10.6) and MCTQ (average MSFsc 201 ± 85 min) scores were suggestive of a previously reported strong general tendency toward morningness in this community. Setting the significance threshold at P > .002 to account for multiple comparisons, we observed a significant association between lower MEQ score (eveningness) and greater volume of the left anterior occipital sulcus (ß = -0.163, p = .001) of the occipital lobe. No significant associations were observed for MCTQ. This may reflect the smaller dataset for MCTQ, and/or the fact that MEQ, which asks questions about preferred timings, is more trait-like than the MCTQ, which asks questions about actual timings. The association between MEQ and a brain region dedicated to visual information processing is suggestive of the increasingly recognized fluidity in the interaction between visual and nonvisual photoreception and the circadian system, and the possibility that chronotype includes an element of masking.
Asunto(s)
Ritmo Circadiano , Vigilia , Encéfalo/diagnóstico por imagen , Brasil , Humanos , Lóbulo Occipital/diagnóstico por imagen , Sueño , Encuestas y CuestionariosRESUMEN
Cardiometabolic risk factors influence white matter hyperintensity (WMH) development: in metabolic syndrome (MetS), higher WMH load is often reported but the relationships between specific cardiometabolic variables, WMH load and cognitive performance are uncertain. We investigated these in a Brazilian sample (aged 50-85) with (N = 61) and without (N = 103) MetS. Stepwise regression models identified effects of cardiometabolic and demographic variables on WMH load (from FLAIR MRI) and verbal recall performance. WMH volume was greater in MetS, but verbal recall performance was not impaired. Age showed the strongest relationship with WMH load. Across all participants, systolic blood pressure (SBP) and fasting blood glucose were also contributors, and WMH volume was negatively associated with verbal recall performance. In non-MetS, higher HbA1c, SBP, and number of MetS components were linked to poorer recall performance while higher triglyceride levels appeared to be protective. In MetS only, these relationships were absent but education exerted a strongly protective effect on recall performance. Thus, results support MetS as a construct: the clustering of cardiometabolic variables in MetS alters their individual relationships with cognition; instead, MetS is characterised by a greater reliance on cognitive reserve mechanisms. In non-MetS, strategies to control HbA1c and SBP should be prioritised as these have the largest impact on cognition.
Asunto(s)
Cognición , Síndrome Metabólico/metabolismo , Síndrome Metabólico/patología , Sustancia Blanca/patología , Sustancia Blanca/fisiopatología , Anciano , Anciano de 80 o más Años , Biomarcadores , Enfermedades Cardiovasculares/complicaciones , Metabolismo Energético , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Síndrome Metabólico/complicaciones , Persona de Mediana Edad , Pruebas Neuropsicológicas , Factores de Riesgo , Sustancia Blanca/diagnóstico por imagenRESUMEN
Individual variability in word generation is a product of genetic and environmental influences. The genetic effects on semantic verbal fluency were estimated in 1,735 participants from the Brazilian Baependi Heart Study. The numbers of exemplars produced in 60 s were broken down into time quartiles because of the involvement of different cognitive processes-predominantly automatic at the beginning, controlled/executive at the end. Heritability in the unadjusted model for the 60-s measure was 0.32. The best-fit model contained age, sex, years of schooling, and time of day as covariates, giving a heritability of 0.21. Schooling had the highest moderating effect. The highest heritability (0.17) was observed in the first quartile, decreasing to 0.09, 0.12, and 0.0003 in the following ones. Heritability for average production starting point (intercept) was 0.18, indicating genetic influences for automatic cognitive processes. Production decay (slope), indicative of controlled processes, was not significant. The genetic influence on different quartiles of the semantic verbal fluency test could potentially be exploited in clinical practice and genome-wide association studies.
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Cognición , Estudio de Asociación del Genoma Completo , Semántica , Conducta Verbal , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana EdadAsunto(s)
Enfermedades Genéticas Congénitas/genética , Femenino , Ligamiento Genético , Técnicas Genéticas , Humanos , Masculino , LinajeRESUMEN
Calcium channels control the inflow of calcium ions into cells and are involved in diverse cellular functions. The CACNA1C gene polymorphism rs1006737 A allele has been strongly associated with increased risk for bipolar disorder (BD) and with modulation of brain morphology. The medial prefrontal cortex (mPFC) has been widely associated with mood regulation in BD, but the role of this CACNA1C polymorphism in mPFC morphology and brain aging has yet to be elucidated. One hundred seventeen euthymic BD type I subjects were genotyped for CACNA1C rs1006737 and underwent 3 T three-dimensional structural magnetic resonance imaging scans to determine cortical thickness of mPFC components (superior frontal cortex (sFC), medial orbitofrontal cortex (mOFC), caudal anterior cingulate cortex (cACC) and rostral anterior cingulate cortex (rACC)). Carriers of the CACNA1C allele A exhibited greater left mOFC thickness compared to non-carriers. Moreover, CACNA1C A carriers showed age-related cortical thinning of the left cACC, whereas among A non-carriers there was not an effect of age on left cACC cortical thinning. In the sFC, mOFC and rACC (left or right), a negative correlation was observed between age and cortical thickness, regardless of CACNA1C rs1006737 A status. Further studies investigating the direct link between cortical thickness, calcium channel function, apoptosis mechanism and their underlying relationship with aging-associated cognitive decline in BD are warranted.
Asunto(s)
Alelos , Trastorno Bipolar/genética , Trastorno Bipolar/patología , Canales de Calcio Tipo L/genética , Predisposición Genética a la Enfermedad/genética , Corteza Prefrontal/patología , Adolescente , Adulto , Factores de Edad , Trastorno Bipolar/diagnóstico por imagen , Dominancia Cerebral/genética , Dominancia Cerebral/fisiología , Femenino , Tamización de Portadores Genéticos , Humanos , Imagenología Tridimensional , Imagen por Resonancia Magnética , Masculino , Polimorfismo Genético/genética , Corteza Prefrontal/diagnóstico por imagen , Estadística como Asunto , Adulto JovenRESUMEN
Recent studies have demonstrated that lithium (Li) exerts neuronal protective and regenerative effects both in vitro and in vivo. However, the effects of long-term Li treatment in the brain areas associated with memory impairment of elderly bipolar patients are still unknown. The aim of this study was to compare the hippocampal volumes of elderly bipolar patients using Li, elderly bipolar patients not using Li and healthy controls. Sociodemographic, clinical and magnetic resonance imaging data from 30 elderly euthymic bipolar patients who had been using Li for an average of >61 months; 27 elderly euthymic bipolar patients not taking Li for an average of 45 months; and 22 elderly healthy controls were analyzed. Volumetric differences in the hippocampus between groups were investigated with voxel-based morphometry (VBM) based on the Statistical Parametric Mapping technique. No statistical differences in sociodemographic and clinical characteristics and course of bipolar disorder between the two bipolar groups were observed. Using small volume correction in the VBM analysis (analysis of variance (ANOVA)), one voxel cluster of statistical significance was detected in the left hippocampus (P<0.05 corrected for multiple comparisons, extent threshold >10 voxels). Post hoc unpaired t-tests revealed increased left hippocampal volume in the Li-treated group compared with the non-Li-treated group, and decreased left hippocampal volume in the non-Li group relative to controls. Additional exploratory two-group comparisons indicated trends toward reduced right-hippocampal volumes in the non-Li-treated group relative to both the Li-treated group and controls. The findings suggested that the use of Li may influence the volume of the hippocampus, possibly due to its neuroprotective effects.
Asunto(s)
Trastorno Bipolar/diagnóstico por imagen , Trastorno Bipolar/tratamiento farmacológico , Hipocampo/efectos de los fármacos , Hipocampo/diagnóstico por imagen , Carbonato de Litio/efectos adversos , Carbonato de Litio/uso terapéutico , Imagen por Resonancia Magnética , Fármacos Neuroprotectores/efectos adversos , Fármacos Neuroprotectores/uso terapéutico , Tamaño de los Órganos/efectos de los fármacos , Factores de Edad , Anciano , Estudios de Casos y Controles , Dominancia Cerebral/efectos de los fármacos , Femenino , Humanos , Cuidados a Largo Plazo , Masculino , Memoria/efectos de los fármacos , Persona de Mediana Edad , Lóbulo Temporal/diagnóstico por imagen , Lóbulo Temporal/efectos de los fármacosRESUMEN
Sleep is modulated by several factors, including sex, age, and chronotype. It has been hypothesised that contemporary urban populations are under pressure towards shorter sleep duration and poorer sleep quality. Baependi is a small town in Brazil that provides a window of opportunity to study the influence of sleep patterns in a highly admixed rural population with a conservative lifestyle. We evaluated sleep characteristics, excessive daytime sleepiness, and chronotype using the Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale and Morningness-Eveningness Questionnaire questionnaires, respectively. The sample consisted of 1,334 subjects from the Baependi Heart study (41.5% male; age: 46.5 ± 16.2 y, range: 18-89 years). Average self-reported sleep duration was 07:07 ± 01:31 (bedtime 22:32 ± 01:27, wake up time: 06:17 ± 01:25 hh:min), sleep quality score was 4.9 + 3.2, chronotype was 63.6 ± 10.8 and daytime sleepiness was 7.4 ± 4.8. Despite a shift towards morningness in the population, chronotype remained associated with reported actual sleep timing. Age and sex modulated the ontogeny of sleep and chronotype, increasing age was associated with earlier sleep time and shorter sleep duration. Women slept longer and later, and reported poorer sleep quality than men (p < 0.0001). This study provides indirect evidence in support of the hypothesis that sleep timing was earlier prior to full urbanisation.
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Higiene del Sueño , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Brasil , Femenino , Humanos , Masculino , Persona de Mediana Edad , Población Rural , Factores Sexuales , Encuestas y Cuestionarios , Factores de Tiempo , Adulto JovenRESUMEN
Linkage and association studies in five independently ascertained samples have suggested that polymorphisms of the regulator of G-protein signaling 4 (RGS4) may confer risk for schizophrenia (SCZ). Suggestive evidence for association with bipolar disorder (BD) has also been presented. However, the associated alleles and haplotypes have differed among the samples. Data from other independent samples may clarify the putative associations. Hence, we investigated an independent, ethnically diverse Brazilian population comprising patients with SCZ (n=271) or BD1 (n=306), who were contrasted with 576 community-based controls. Parents of 49 SCZ cases and 44 BD cases were available for transmission disequilibrium tests (TDTs). Four RGS4 single-nucleotide polymorphisms (SNPs) 1, 4, 7 and 18 putatively associated with SCZ were investigated. In the SCZ samples, significant case-control differences were not observed for individual SNPs or haplotypes, though the TDT suggested transmission distortion similar to that observed in the initial report. For the BD sample, case-control comparisons revealed no significant differences for individual SNPs, but an omnibus test suggested differences in the overall distribution of haplotypes bearing all four SNPs (SNP-EM Omnibus likelihood ratio test; P=0.003). The TDT revealed over-transmission of allele A at SNP7 (P=0.016), as well as haplotypes incorporating this allele. However, global tests incorporating all haplotypes yielded only suggestive trends for association (P=0.19). In conclusion, association with SCZ was not detected in the present analyses. The failure to detect an association may be related to inadequate power or to confounds related to ethnic admixture. Suggestive associations with BD detected here require further investigation in a larger sample.
Asunto(s)
Trastorno Bipolar/genética , Haplotipos , Polimorfismo de Nucleótido Simple/genética , Proteínas RGS/genética , Esquizofrenia/genética , Adulto , Brasil , Estudios de Casos y Controles , Femenino , Predisposición Genética a la Enfermedad , Humanos , Desequilibrio de Ligamiento , Masculino , Persona de Mediana Edad , Linaje , Valores de ReferenciaRESUMEN
Family and twin studies have supported a strong genetic factor in the etiology of obsessive-compulsive disorder (OCD), although the precise mechanism of inheritance is unclear. Clinical and pharmacological studies have implicated the serotonergic and dopaminergic systems in disease pathogenesis. In this cross-sectional study, we have examined the allelic and genotypic frequencies of a Val-158-Met substitution in the COMT gene, a 44-base pair (bp) length variation in the regulatory region of the serotonin transporter gene (5-HTTLPR) and the T102C and C516T variants in the serotonin receptor type 2A (5HT2A) gene in 79 OCD patients and 202 control subjects. There were no observed differences in the frequencies of allele and genotype between patients and control groups for the COMT, the 5HTTLPR and the T102C 5HT2A gene polymorphisms. In contrast, a statistically significant difference between OCD patients and controls was observed on the genotypic distribution (chi(2) = 16.7, 2df, P = 0.0002) and on the allelic frequencies (chi(2) = 15.8, 1df, P = 0.00007) for the C516T 5HT2A gene polymorphism. The results suggest that the C516T variant of the 5HT2A gene may be one of the genetic risk factors for OCD in our sample. However, further studies using larger samples and family based methods are recommended to confirm these findings.
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Proteínas Portadoras/genética , Catecol O-Metiltransferasa/genética , Glicoproteínas de Membrana/genética , Proteínas de Transporte de Membrana , Proteínas del Tejido Nervioso , Trastorno Obsesivo Compulsivo/genética , Polimorfismo Genético/genética , Receptor de Serotonina 5-HT2A/genética , Adulto , Sustitución de Aminoácidos/genética , Estudios de Casos y Controles , Femenino , Frecuencia de los Genes , Humanos , Masculino , Valores de Referencia , Secuencias Reguladoras de Ácidos Nucleicos/genética , Proteínas de Transporte de Serotonina en la Membrana PlasmáticaRESUMEN
Catechol-O-methyltransferase catalyses the O-methylation of biologically active or toxic catechols and is a major component of the metabolism of drugs and neurotransmitters such as L-dopa, noradrenaline, adrenaline, and dopamine. Human catechol-O-methyltransferase activity is an autosomal partially dominant trait and is strongly associated with a valine to methionine substitution at codon 158 of the protein. About 25% of Caucasians have low activity, 50% intermediate activity and 25% high activity as determined by either phenotypic or genotypic measurement. In black populations, the low activity allele (Met158; COMTL) is less frequent with about 7% being homozygous. Using a PCR based genotyping assay, we report that the Met158 allele is also less frequent in normal Han Chinese subjects with about 3% of the population being homozygous. Because of its role in catecholamine metabolism and several lines of evidence pointing to a locus for psychosis near the COMT gene on chromosome 22q11, we have analysed the COMT Val158Met polymorphism as a candidate susceptibility factor for bipolar affective disorder. We report an association between bipolar affective disorder and the Met158 allele (p = 0.004) and genotype (p = 0.01) in 93 affected Chinese subjects and 98 controls. We hypothesize that either the low activity allele of catechol-O-methyltransferase is a risk factor for bipolar affective disorder in Chinese populations or is in linkage disequilibrium with a nearby susceptibility gene or polymorphism.
Asunto(s)
Trastorno Bipolar/genética , Catecol O-Metiltransferasa/genética , Metionina/genética , Mutación Puntual , Polimorfismo Genético , Valina/genética , China/etnología , Femenino , Predisposición Genética a la Enfermedad , Humanos , MasculinoRESUMEN
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.
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Catecol O-Metiltransferasa/genética , Trastornos del Humor/genética , Adulto , Alelos , Trastorno Bipolar/genética , Trastorno Bipolar/psicología , Trastorno Depresivo/genética , Trastorno Depresivo/psicología , Genotipo , Humanos , Trastornos del Humor/psicología , Reacción en Cadena de la Polimerasa , Polimorfismo GenéticoRESUMEN
BACKGROUND: Family studies of schizophrenia and bipolar affective disorder provide evidence for genetic anticipation, which (in common with a number of mendelian disorders), may be caused by triplet repeat expansion. This hypothesis is strengthened by evidence from repeat expansion detection (RED) analysis revealing association between the psychoses and long CAG/CTG trinucleotide repeats. METHODS: We performed RED on Han Chinese subjects with schizophrenia (82), bipolar affective disorder (43), and normal controls (61), using a CTG10 oligonucleotide. RESULTS: Comparison between cases and controls revealed no significant association between long repeats and affected status. We also found no detectable association with age at onset and repeat length in either bipolar affective disorder or schizophrenia. Overall, the size distribution of CAG/CTG repeats in Chinese subjects was not significantly different from those reported previously for Caucasian subjects. CONCLUSIONS: These findings indicate that CAG/CTG repeat expansion is not likely to be a major etiological factor for psychosis in Chinese populations.
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Trastorno Bipolar/genética , Esquizofrenia/genética , Expansión de Repetición de Trinucleótido/genética , Adolescente , Adulto , Alelos , Trastorno Bipolar/etnología , China , Femenino , Humanos , Masculino , Esquizofrenia/etnología , Factores SexualesRESUMEN
As part of a systematic search for a major genetic locus for schizophrenia we have examined chromosome 22 using 14 highly polymorphic markers in 23 disease pedigrees. The markers were distributed at an average distance of 6.6 cM, covering 70-80% of the chromosome. We analyzed the data by the lod score method using five plausible genetic models ranging from dominant to recessive, after testing the power of our sample under the same genetic parameters. The most positive lod score found was 1.51 under a recessive model for the marker D22S278, which is insufficient to conclude linkage. However, an excess of shared alleles in affected siblings (P < .01) was found for both D22S278 and D22S283. For D22S278, the A statistic was equal to the lod score (1.51) and therefore did not provide additional evidence for linkage allowing for heterogeneity, but the Liang statistic was more significant (P = .002). Our results suggest the possibility that the region around D22S278 and D22S283 contains a gene which contributes to the aetiology of schizophrenia.
Asunto(s)
Cromosomas Humanos Par 22/genética , Ligamiento Genético , Esquizofrenia/genética , Alelos , Secuencia de Bases , Mapeo Cromosómico , Cartilla de ADN/genética , Femenino , Marcadores Genéticos , Humanos , Escala de Lod , Masculino , Modelos Genéticos , Datos de Secuencia Molecular , Linaje , Polimorfismo GenéticoRESUMEN
Evidence consistent with the existence of genetic linkage between bipolar disorder and three regions on chromosome 18, the pericentromeric region, 18q21, and 18q22-q23 have been reported. Some analyses indicated greater evidence for linkage in pedigrees in which paternal transmission of disease occurs. We have undertaken linkage analyses using 12 highly polymorphic markers spanning these three regions of interest in a sample of 48 U.K. bipolar pedigrees. The sample comprises predominantly nuclear families and includes 118 subjects with Diagnostic and Statistical Manual of Mental Disorders (DSM IV) bipolar I disorder and 147 subjects with broadly defined phenotype. Our data do not provide support for linkage using either parametric or nonparametric analyses. Evidence for linkage was not significantly increased by analyses that allowed for heterogeneity nor by analysing the subset of pedigrees consistent with paternal transmission.
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Trastorno Bipolar/genética , Cromosomas Humanos Par 18 , Ligamiento Genético , Femenino , Marcadores Genéticos , Predisposición Genética a la Enfermedad , Humanos , Escala de Lod , Masculino , Repeticiones de Microsatélite , Polimorfismo GenéticoRESUMEN
It has been suggested that the serotonin transporter (5-hydroxytryptamine-transporter or 5-HTT) may be involved in the pathogenesis of affective disorders. Recently, Collier et al. (1996) found that the frequency of the low-activity short variant (s) of the 5-HTT-linked polymorphic region (5-HTTLPR) was higher among patients with affective disorders than in normal controls. However, since the observed level of significance was not high, they suggest that these findings should be replicated in independent samples. We have analyzed 86 unrelated patients (47 with bipolar disorder and 39 with schizophrenia) and 98 normal controls from the Brazilian population for the 5-HTTLPR. Statistical analysis revealed that the genotypes (LL, Ls, ss) as well as the estimated allele frequencies (L,s) did not differ significantly among the three studied groups or between bipolar and normal controls. In addition, although not statistically significant, the genotype ss in our sample was less frequent among our bipolar patients than in our normal controls (12.8% versus 16.3%) which is the opposite of what was found by Collier et al. (24% versus 18%) in the European study. Although it will be important to extend the present analysis in a larger sample, our preliminary results suggest that the 5-HTTLPR does not seem to play a major role in the genetics of bipolar and schizophrenic disorders at least in this group of Brazilian psychiatric patients.
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Trastorno Bipolar/genética , Proteínas Portadoras/genética , Glicoproteínas de Membrana/genética , Proteínas de Transporte de Membrana , Proteínas del Tejido Nervioso , Polimorfismo Genético , Regiones Promotoras Genéticas/genética , Esquizofrenia/genética , Trastorno Bipolar/etnología , Brasil/etnología , Frecuencia de los Genes , Genes/genética , Genotipo , Humanos , Esquizofrenia/etnología , Proteínas de Transporte de Serotonina en la Membrana PlasmáticaRESUMEN
Several groups have reported weak evidence for linkage between schizophrenia and genetic markers located on chromosome 22q using the lod score method of analysis. However these findings involved different genetic markers and methods of analysis, and so were not directly comparable. To resolve this issue we have performed a combined analysis of genotypic data from the marker D22S278 in multiply affected schizophrenic families derived from 11 independent research groups worldwide. This marker was chosen because it showed maximum evidence for linkage in three independent datasets (Vallada et al., Am J Med Genet 60:139-146, 1995; Polymeropoulos et al., Neuropsychiatr Genet 54:93-99, 1994; Lasseter et al., Am J Med Genet, 60:172-173, 1995. Using the affected sib-pair method as implemented by the program ESPA, the combined dataset showed 252 alleles shared compared with 188 alleles not share (chi-square 9.31, 1df, P = 0.001) where parental genotype data was completely known. When sib-pairs for whom parental data was assigned according to probability were included the number of alleles shared was 514.1 compared with 437.8 not shared (chi-square 6.12, 1df, P = 0.006). Similar results were obtained when a likelihood ratio method for sib-pair analysis was used. These results indicate that may be a susceptibility locus for schizophrenia at 22q12.
Asunto(s)
Alelos , Cromosomas Humanos Par 22 , Esquizofrenia/genética , Mapeo Cromosómico , Susceptibilidad a Enfermedades , Heterogeneidad Genética , Marcadores Genéticos , HumanosRESUMEN
The 1995 World Congress on Psychiatric Genetics was held in Cardiff, UK, from August 29th to September 1st 1995. Two hundred and forty-seven posters were presented wherein approximately 130 studies were on schizophrenia. An overview of them is reported here. The abstracts of these studies are published in Psychiatric Genetics (vol. 5, suppl. 1, 1995).
Asunto(s)
Cromosomas Humanos Par 22 , Cromosomas Humanos Par 6 , Esquizofrenia/genética , Ligamiento Genético/genética , Humanos , GalesRESUMEN
Two recent genome-wide searches for linkage (Lasseter et al., 1994; Moises et al., 1995) suggested that a susceptibility gene for schizophrenia might be located at chromosome 8p21-p22. We attempted to replicate these findings by performing a linkage study of schizophrenia with four DNA markers from this region using 25 multiply affected families. Neither the lod score method nor non-prametric extended sib-pair analysis yielded any evidence for linkage, even under the assumption of locus heterogeneity. We conclude that there is unlikely to be a major gene in the 8p21-p22 region which confers susceptibility to schizophrenia in our set of families. However we cannot exclude the possibility of a major gene present in other families, or of a susceptibility gene with a moderate but widespread effect which we cannot detect.