Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 43
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Mol Psychiatry ; 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31492941

RESUMO

Based on the discovery by the Resilience Project (Chen R. et al. Nat Biotechnol 34:531-538, 2016) of rare variants that confer resistance to Mendelian disease, and protective alleles for some complex diseases, we posited the existence of genetic variants that promote resilience to highly heritable polygenic disorders1,0 such as schizophrenia. Resilience has been traditionally viewed as a psychological construct, although our use of the term resilience refers to a different construct that directly relates to the Resilience Project, namely: heritable variation that promotes resistance to disease by reducing the penetrance of risk loci, wherein resilience and risk loci operate orthogonal to one another. In this study, we established a procedure to identify unaffected individuals with relatively high polygenic risk for schizophrenia, and contrasted them with risk-matched schizophrenia cases to generate the first known "polygenic resilience score" that represents the additive contributions to SZ resistance by variants that are distinct from risk loci. The resilience score was derived from data compiled by the Psychiatric Genomics Consortium, and replicated in three independent samples. This work establishes a generalizable framework for finding resilience variants for any complex, heritable disorder.

2.
Nat Genet ; 51(5): 793-803, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31043756

RESUMO

Bipolar disorder is a highly heritable psychiatric disorder. We performed a genome-wide association study (GWAS) including 20,352 cases and 31,358 controls of European descent, with follow-up analysis of 822 variants with P < 1 × 10-4 in an additional 9,412 cases and 137,760 controls. Eight of the 19 variants that were genome-wide significant (P < 5 × 10-8) in the discovery GWAS were not genome-wide significant in the combined analysis, consistent with small effect sizes and limited power but also with genetic heterogeneity. In the combined analysis, 30 loci were genome-wide significant, including 20 newly identified loci. The significant loci contain genes encoding ion channels, neurotransmitter transporters and synaptic components. Pathway analysis revealed nine significantly enriched gene sets, including regulation of insulin secretion and endocannabinoid signaling. Bipolar I disorder is strongly genetically correlated with schizophrenia, driven by psychosis, whereas bipolar II disorder is more strongly correlated with major depressive disorder. These findings address key clinical questions and provide potential biological mechanisms for bipolar disorder.


Assuntos
Transtorno Bipolar/genética , Loci Gênicos , Transtorno Bipolar/classificação , Estudos de Casos e Controles , Transtorno Depressivo Maior/genética , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Transtornos Psicóticos/genética , Esquizofrenia/genética , Biologia de Sistemas
3.
Nat Genet ; 51(3): 404-413, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30617256

RESUMO

Alzheimer's disease (AD) is highly heritable and recent studies have identified over 20 disease-associated genomic loci. Yet these only explain a small proportion of the genetic variance, indicating that undiscovered loci remain. Here, we performed a large genome-wide association study of clinically diagnosed AD and AD-by-proxy (71,880 cases, 383,378 controls). AD-by-proxy, based on parental diagnoses, showed strong genetic correlation with AD (rg = 0.81). Meta-analysis identified 29 risk loci, implicating 215 potential causative genes. Associated genes are strongly expressed in immune-related tissues and cell types (spleen, liver, and microglia). Gene-set analyses indicate biological mechanisms involved in lipid-related processes and degradation of amyloid precursor proteins. We show strong genetic correlations with multiple health-related outcomes, and Mendelian randomization results suggest a protective effect of cognitive ability on AD risk. These results are a step forward in identifying the genetic factors that contribute to AD risk and add novel insights into the neurobiology of AD.


Assuntos
Doença de Alzheimer/genética , Predisposição Genética para Doença/genética , Locos de Características Quantitativas/genética , Adulto , Estudos de Casos e Controles , Feminino , Estudo de Associação Genômica Ampla/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Risco , Adulto Jovem
4.
Sci Rep ; 8(1): 18088, 2018 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-30591712

RESUMO

A large fraction of genetic risk factors for Alzheimer's Disease (AD) is still not identified, limiting the understanding of AD pathology and study of therapeutic targets. We conducted a genome-wide association study (GWAS) of AD cases and controls of European descent from the multi-center DemGene network across Norway and two independent European cohorts. In a two-stage process, we first performed a meta-analysis using GWAS results from 2,893 AD cases and 6,858 cognitively normal controls from Norway and 25,580 cases and 48,466 controls from the International Genomics of Alzheimer's Project (IGAP), denoted the discovery sample. Second, we selected the top hits (p < 1 × 10-6) from the discovery analysis for replication in an Icelandic cohort consisting of 5,341 cases and 110,008 controls. We identified a novel genomic region with genome-wide significant association with AD on chromosome 4 (combined analysis OR = 1.07, p = 2.48 x 10-8). This finding implicated HS3ST1, a gene expressed throughout the brain particularly in the cerebellar cortex. In addition, we identified IGHV1-68 in the discovery sample, previously not associated with AD. We also associated USP6NL/ECHDC3 and BZRAP1-AS1 to AD, confirming findings from a follow-up transethnic study. These new gene loci provide further evidence for AD as a polygenic disorder, and suggest new mechanistic pathways that warrant further investigation.


Assuntos
Doença de Alzheimer/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Locos de Características Quantitativas , Adolescente , Adulto , Idoso , Biomarcadores , Estudos de Casos e Controles , Feminino , Estudos de Associação Genética/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Noruega , Polimorfismo de Nucleotídeo Único , Adulto Jovem
5.
Nat Commun ; 9(1): 3456, 2018 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-30150678

RESUMO

Discovery of coding variants in genes that confer risk of neurodevelopmental disorders is an important step towards understanding the pathophysiology of these disorders. Whole-genome sequencing of 31,463 Icelanders uncovers a frameshift variant (E712KfsTer10) in microtubule-associated protein 1B (MAP1B) that associates with ID/low IQ in a large pedigree (genome-wide corrected P = 0.022). Additional stop-gain variants in MAP1B (E1032Ter and R1664Ter) validate the association with ID and IQ. Carriers have 24% less white matter (WM) volume (ß = -2.1SD, P = 5.1 × 10-8), 47% less corpus callosum (CC) volume (ß = -2.4SD, P = 5.5 × 10-10) and lower brain-wide fractional anisotropy (P = 6.7 × 10-4). In summary, we show that loss of MAP1B function affects general cognitive ability through a profound, brain-wide WM deficit with likely disordered or compromised axons.

6.
Addict Biol ; 23(1): 485-492, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28231610

RESUMO

We use polygenic risk scores (PRSs) for schizophrenia (SCZ) and bipolar disorder (BPD) to predict smoking, and addiction to nicotine, alcohol or drugs in individuals not diagnosed with psychotic disorders. Using PRSs for 144 609 subjects, including 10 036 individuals admitted for in-patient addiction treatment and 35 754 smokers, we find that diagnoses of various substance use disorders and smoking associate strongly with PRSs for SCZ (P = 5.3 × 10-50 -1.4 × 10-6 ) and BPD (P = 1.7 × 10-9 -1.9 × 10-3 ), showing shared genetic etiology between psychosis and addiction. Using standardized scores for SCZ and BPD scaled to a unit increase doubling the risk of the corresponding disorder, the odds ratios for alcohol and substance use disorders range from 1.19 to 1.31 for the SCZ-PRS, and from 1.07 to 1.29 for the BPD-PRS. Furthermore, we show that as regular smoking becomes more stigmatized and less prevalent, these biological risk factors gain importance as determinants of the behavior.

7.
Nat Genet ; 49(8): 1251-1254, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28628109

RESUMO

Thus far, a handful of highly penetrant mutations conferring risk of psychosis have been discovered. Here we used whole-genome sequencing and long-range phasing to investigate an Icelandic kindred containing ten individuals with psychosis (schizophrenia, schizoaffective disorder or psychotic bipolar disorder). We found that all affected individuals carry RBM12 (RNA-binding-motif protein 12) c.2377G>T (P = 2.2 × 10-4), a nonsense mutation that results in the production of a truncated protein lacking a predicted RNA-recognition motif. We replicated the association in a Finnish family in which a second RBM12 truncating mutation (c.2532delT) segregates with psychosis (P = 0.020). c.2377G>T is not fully penetrant for psychosis; however, we found that carriers unaffected by psychosis resemble patients with schizophrenia in their non-psychotic psychiatric disorder and neuropsychological test profile (P = 0.0043) as well as in their life outcomes (including an increased chance of receiving disability benefits, P = 0.011). As RBM12 has not previously been linked to psychosis, this work provides new insight into psychiatric disease.


Assuntos
Códon sem Sentido , Transtornos Psicóticos/genética , Proteínas de Ligação a RNA/genética , Saúde da Família , Feminino , Genoma Humano , Humanos , Islândia , Masculino , Análise de Sequência de DNA
8.
Biol Psychiatry ; 81(4): 325-335, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-27519822

RESUMO

BACKGROUND: Major depressive disorder (MDD) is a disabling mood disorder, and despite a known heritable component, a large meta-analysis of genome-wide association studies revealed no replicable genetic risk variants. Given prior evidence of heterogeneity by age at onset in MDD, we tested whether genome-wide significant risk variants for MDD could be identified in cases subdivided by age at onset. METHODS: Discovery case-control genome-wide association studies were performed where cases were stratified using increasing/decreasing age-at-onset cutoffs; significant single nucleotide polymorphisms were tested in nine independent replication samples, giving a total sample of 22,158 cases and 133,749 control subjects for subsetting. Polygenic score analysis was used to examine whether differences in shared genetic risk exists between earlier and adult-onset MDD with commonly comorbid disorders of schizophrenia, bipolar disorder, Alzheimer's disease, and coronary artery disease. RESULTS: We identified one replicated genome-wide significant locus associated with adult-onset (>27 years) MDD (rs7647854, odds ratio: 1.16, 95% confidence interval: 1.11-1.21, p = 5.2 × 10-11). Using polygenic score analyses, we show that earlier-onset MDD is genetically more similar to schizophrenia and bipolar disorder than adult-onset MDD. CONCLUSIONS: We demonstrate that using additional phenotype data previously collected by genetic studies to tackle phenotypic heterogeneity in MDD can successfully lead to the discovery of genetic risk factor despite reduced sample size. Furthermore, our results suggest that the genetic susceptibility to MDD differs between adult- and earlier-onset MDD, with earlier-onset cases having a greater genetic overlap with schizophrenia and bipolar disorder.


Assuntos
Transtorno Depressivo Maior/epidemiologia , Transtorno Depressivo Maior/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Adulto , Idade de Início , Transtorno Bipolar/epidemiologia , Transtorno Bipolar/genética , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Herança Multifatorial , Fenótipo , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Esquizofrenia/epidemiologia , Esquizofrenia/genética , Adulto Jovem
10.
Nat Genet ; 48(8): 856-66, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27322543

RESUMO

Migraine is a debilitating neurological disorder affecting around one in seven people worldwide, but its molecular mechanisms remain poorly understood. There is some debate about whether migraine is a disease of vascular dysfunction or a result of neuronal dysfunction with secondary vascular changes. Genome-wide association (GWA) studies have thus far identified 13 independent loci associated with migraine. To identify new susceptibility loci, we carried out a genetic study of migraine on 59,674 affected subjects and 316,078 controls from 22 GWA studies. We identified 44 independent single-nucleotide polymorphisms (SNPs) significantly associated with migraine risk (P < 5 × 10(-8)) that mapped to 38 distinct genomic loci, including 28 loci not previously reported and a locus that to our knowledge is the first to be identified on chromosome X. In subsequent computational analyses, the identified loci showed enrichment for genes expressed in vascular and smooth muscle tissues, consistent with a predominant theory of migraine that highlights vascular etiologies.


Assuntos
Loci Gênicos/genética , Marcadores Genéticos/genética , Predisposição Genética para Doença , Transtornos de Enxaqueca/genética , Polimorfismo de Nucleotídeo Único/genética , Estudos de Casos e Controles , Estudo de Associação Genômica Ampla , Genômica , Humanos , Músculo Liso/metabolismo , Doenças Vasculares/genética
11.
Am J Hum Genet ; 98(5): 898-908, 2016 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-27132594

RESUMO

Spontaneous dizygotic (DZ) twinning occurs in 1%-4% of women, with familial clustering and unknown physiological pathways and genetic origin. DZ twinning might index increased fertility and has distinct health implications for mother and child. We performed a GWAS in 1,980 mothers of spontaneous DZ twins and 12,953 control subjects. Findings were replicated in a large Icelandic cohort and tested for association across a broad range of fertility traits in women. Two SNPs were identified (rs11031006 near FSHB, p = 1.54 × 10(-9), and rs17293443 in SMAD3, p = 1.57 × 10(-8)) and replicated (p = 3 × 10(-3) and p = 1.44 × 10(-4), respectively). Based on ∼90,000 births in Iceland, the risk of a mother delivering twins increased by 18% for each copy of allele rs11031006-G and 9% for rs17293443-C. A higher polygenic risk score (PRS) for DZ twinning, calculated based on the results of the DZ twinning GWAS, was significantly associated with DZ twinning in Iceland (p = 0.001). A higher PRS was also associated with having children (p = 0.01), greater lifetime parity (p = 0.03), and earlier age at first child (p = 0.02). Allele rs11031006-G was associated with higher serum FSH levels, earlier age at menarche, earlier age at first child, higher lifetime parity, lower PCOS risk, and earlier age at menopause. Conversely, rs17293443-C was associated with later age at last child. We identified robust genetic risk variants for DZ twinning: one near FSHB and a second within SMAD3, the product of which plays an important role in gonadal responsiveness to FSH. These loci contribute to crucial aspects of reproductive capacity and health.


Assuntos
Fertilidade/genética , Variação Genética/genética , Síndrome do Ovário Policístico/genética , Gêmeos Dizigóticos/genética , Ansiedade/genética , Estudos de Casos e Controles , Depressão/genética , Família , Feminino , Hormônio Foliculoestimulante/sangue , Estudo de Associação Genômica Ampla , Humanos , Estudos Longitudinais , Masculino , Mães , Síndrome do Ovário Policístico/sangue , Gravidez
12.
Biol Psychiatry ; 79(5): 383-391, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26444075

RESUMO

BACKGROUND: Gilles de la Tourette syndrome (GTS) is a complex neuropsychiatric disorder with a strong genetic influence where copy number variations are suggested to play a role in disease pathogenesis. In a previous small-scale copy number variation study of a GTS cohort (n = 111), recurrent exon-affecting microdeletions of four genes, including the gene encoding arylacetamide deacetylase (AADAC), were observed and merited further investigations. METHODS: We screened a Danish cohort of 243 GTS patients and 1571 control subjects for submicroscopic deletions and duplications of these four genes. The most promising candidate gene, AADAC, identified in this Danish discovery sample was further investigated in cohorts from Iceland, the Netherlands, Hungary, Germany, and Italy, and a final meta-analysis, including a total of 1181 GTS patients and 118,730 control subjects from these six European countries, was performed. Subsequently, expression of the candidate gene in the central nervous system was investigated using human and mouse brain tissues. RESULTS: In the Danish cohort, we identified eight patients with overlapping deletions of AADAC. Investigation of the additional five countries showed a significant association between the AADAC deletion and GTS, and a final meta-analysis confirmed the significant association (p = 4.4 × 10(-4); odds ratio = 1.9; 95% confidence interval = 1.33-2.71). Furthermore, RNA in situ hybridization and reverse transcription-polymerase chain reaction studies revealed that AADAC is expressed in several brain regions previously implicated in GTS pathology. CONCLUSIONS: AADAC is a candidate susceptibility factor for GTS and the present findings warrant further genomic and functional studies to investigate the role of this gene in the pathogenesis of GTS.


Assuntos
Variações do Número de Cópias de DNA/genética , Deleção de Sequência/genética , Síndrome de Tourette/genética , Adulto , Animais , Transtorno do Deficit de Atenção com Hiperatividade/genética , Estudos de Coortes , Comorbidade , Dinamarca , Éxons , Feminino , Técnicas de Genotipagem , Alemanha , Humanos , Hungria , Islândia , Itália , Masculino , Camundongos , Países Baixos
13.
Cephalalgia ; 36(7): 615-23, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25667298

RESUMO

INTRODUCTION: The objective of the study was to follow up and to test whether 12 previously identified migraine-associated single nucleotide polymorphisms were associated as risk factors and/or modifying factors for severe migraine traits in a Danish clinic-based population. METHODS: Semi-structured migraine interviews, blood sampling and genotyping were performed on 1806 unrelated migraineurs recruited from the Danish Headache Center. Genotyping was also performed on a control group of 6415 people with no history of migraine. Association analyses were carried out using logistic regression and odds ratios were calculated assuming an additive model for risk. The proxies for severe migraine traits (early onset of migraine; many lifetime attacks, prolonged migraine and tendency to chronification of migraine) were tested against the 12 single nucleotide polymorphisms and a combined genetic score in both a case-control and case-only logistic regression model. RESULTS: We successfully replicated five out of the 12 previously reported loci and confirmed the same direction of effects for all the 12 single nucleotide polymorphisms. In line with the recently published genome-wide association meta-analysis, the associations were significant for all migraine and migraine without aura but not for migraine with typical aura. Two single nucleotide polymorphisms (rs2274316 and rs11172113) conferred risk of many lifetime attacks inthe case-control analysis. In the case-only analysis, only three single nucleotide polymorphisms showed nominal association with many lifetime attacks and prolonged migraine attacks. CONCLUSION: Our study supports previously reported findings on the association of several single nucleotide polymorphisms with migraine. It also suggests that the migraine susceptibility loci may be risk factors for severe migraine traits.


Assuntos
Predisposição Genética para Doença/genética , Transtornos de Enxaqueca/genética , Adulto , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Polimorfismo de Nucleotídeo Único , Fatores de Risco
14.
Hum Mol Genet ; 24(19): 5637-43, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26188007

RESUMO

Together with point mutations, homozygous deletions or duplications in PARK2 are responsible for the majority of autosomal recessive juvenile Parkinsonism. It is debated, however, whether heterozygous carriers of these mutations are at increased risk of Parkinson's disease (PD). Our goal was to determine whether heterozygous carriers of copy number variants (CNVs) affecting exons of the PARK2 gene are at risk of PD that is greater than that of non-carriers. We searched for CNVs affecting exons of PARK2 in a sample of 105 749 genotyped Icelanders. In total, 989 carriers, including 24 diagnosed with PD, were identified. The heterozygous carriers were tested for association in a sample of 1415 PD patients and 40 474 controls ≥65 years of age. PD patients were more often heterozygous carriers of PARK2 CNVs than controls [odds ratio (OR) = 1.69, P = 0.03] and compound heterozygous PD patients for a CNV and a missense mutation were not found. Furthermore, we conducted a meta-analysis of studies reporting on case-control samples screened for heterozygous PARK2 CNVs. Ten studies were included in the final analysis, with 4538 cases and 4213 controls. The pooled OR and P-value for the published and Icelandic results showed significant association between PARK2 CNVs and risk of PD (OR = 2.11, P = 2.54 × 10(-6)). Our analysis shows that heterozygous carriers of CNVs affecting exons of PARK2 have greater risk of PD than non-carriers.


Assuntos
Variações do Número de Cópias de DNA , Heterozigoto , Doença de Parkinson/genética , Ubiquitina-Proteína Ligases/genética , Idoso , Idoso de 80 Anos ou mais , Grupo com Ancestrais do Continente Europeu/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Islândia
15.
Nat Neurosci ; 18(7): 953-5, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26053403

RESUMO

We tested whether polygenic risk scores for schizophrenia and bipolar disorder would predict creativity. Higher scores were associated with artistic society membership or creative profession in both Icelandic (P = 5.2 × 10(-6) and 3.8 × 10(-6) for schizophrenia and bipolar disorder scores, respectively) and replication cohorts (P = 0.0021 and 0.00086). This could not be accounted for by increased relatedness between creative individuals and those with psychoses, indicating that creativity and psychosis share genetic roots.


Assuntos
Transtorno Bipolar/genética , Criatividade , Predisposição Genética para Doença/genética , Herança Multifatorial/genética , Transtornos Psicóticos/genética , Sistema de Registros , Esquizofrenia/genética , Estudos de Coortes , Feminino , Humanos , Islândia/epidemiologia , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Risco , Suécia/epidemiologia
16.
Circulation ; 131(23): 2061-2069, 2015 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-25862742

RESUMO

BACKGROUND: Epidemiological findings suggest a relationship between Alzheimer disease (AD), inflammation, and dyslipidemia, although the nature of this relationship is not well understood. We investigated whether this phenotypic association arises from a shared genetic basis. METHODS AND RESULTS: Using summary statistics (P values and odds ratios) from genome-wide association studies of >200 000 individuals, we investigated overlap in single-nucleotide polymorphisms associated with clinically diagnosed AD and C-reactive protein (CRP), triglycerides, and high- and low-density lipoprotein levels. We found up to 50-fold enrichment of AD single-nucleotide polymorphisms for different levels of association with C-reactive protein, low-density lipoprotein, high-density lipoprotein, and triglyceride single-nucleotide polymorphisms using a false discovery rate threshold <0.05. By conditioning on polymorphisms associated with the 4 phenotypes, we identified 55 loci associated with increased AD risk. We then conducted a meta-analysis of these 55 variants across 4 independent AD cohorts (total: n=29 054 AD cases and 114 824 healthy controls) and discovered 2 genome-wide significant variants on chromosome 4 (rs13113697; closest gene, HS3ST1; odds ratio=1.07; 95% confidence interval=1.05-1.11; P=2.86×10(-8)) and chromosome 10 (rs7920721; closest gene, ECHDC3; odds ratio=1.07; 95% confidence interval=1.04-1.11; P=3.38×10(-8)). We also found that gene expression of HS3ST1 and ECHDC3 was altered in AD brains compared with control brains. CONCLUSIONS: We demonstrate genetic overlap between AD, C-reactive protein, and plasma lipids. By conditioning on the genetic association with the cardiovascular phenotypes, we identify novel AD susceptibility loci, including 2 genome-wide significant variants conferring increased risk for AD.


Assuntos
Doença de Alzheimer/genética , Proteína C-Reativa/metabolismo , Dislipidemias/genética , Estudo de Associação Genômica Ampla , Inflamação/genética , Lipídeos/sangue , Herança Multifatorial/genética , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/epidemiologia , Biomarcadores/metabolismo , Encéfalo/metabolismo , Proteína C-Reativa/genética , Dislipidemias/complicações , Feminino , Humanos , Inflamação/complicações , Lipídeos/genética , Masculino , Enzima Bifuncional do Peroxissomo/genética , Enzima Bifuncional do Peroxissomo/metabolismo , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Fatores de Risco , Sulfotransferases/genética , Sulfotransferases/metabolismo
17.
Nat Genet ; 47(5): 445-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25807283

RESUMO

We conducted a search for rare, functional variants altering susceptibility to Alzheimer's disease that exploited knowledge of common variants associated with the same disease. We found that loss-of-function variants in ABCA7 confer risk of Alzheimer's disease in Icelanders (odds ratio (OR) = 2.12, P = 2.2 × 10(-13)) and discovered that the association replicated in study groups from Europe and the United States (combined OR = 2.03, P = 6.8 × 10(-15)).


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Doença de Alzheimer/genética , Estudos de Casos e Controles , Estudos de Associação Genética , Predisposição Genética para Doença , Haplótipos , Humanos , Mutação , Risco , Análise de Sequência de DNA
18.
Biol Psychiatry ; 76(2): 128-37, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24090792

RESUMO

BACKGROUND: Genome-wide scans have uncovered rare copy number variants conferring high risk of psychiatric disorders. The 15q13.3 microdeletion is associated with a considerably increased risk of idiopathic generalized epilepsy, intellectual disability, and schizophrenia. METHODS: A 15q13.3 microdeletion mouse model (Df[h15q13]/+) was generated by hemizygous deletion of the orthologous region and characterized with focus on schizophrenia- and epilepsy-relevant parameters. RESULTS: Df(h15q13)/+ mice showed marked changes in neuronal excitability in acute seizure assays, with increased propensity to develop myoclonic and absence-like seizures but decreased propensity for clonic and tonic seizures. Furthermore, they had impaired long-term spatial reference memory and a decreased theta frequency in hippocampus and prefrontal cortex. Electroencephalogram characterization revealed auditory processing deficits similar to those observed in schizophrenia. Gamma band power was increased during active state, but evoked gamma power following auditory stimulus (40 Hz) was dramatically reduced, mirroring observations in patients with schizophrenia. In addition, Df(h15q13)/+ mice showed schizophrenia-like decreases in amplitudes of auditory evoked potentials. Although displaying a grossly normal behavior, Df(h15q13)/+ mice are more aggressive following exposure to mild stressors, similar to what is described in human deletion carriers. Furthermore, Df(h15q13)/+ mice have increased body weight, and a similar increase in body weight was subsequently found in a sample of human subjects with 15q13.3 deletion. CONCLUSIONS: The Df(h15q13)/+ mouse shows similarities to several alterations related to the 15q13.3 microdeletion syndrome, epilepsy, and schizophrenia, offering a novel tool for addressing the underlying biology of these diseases.


Assuntos
Encéfalo/fisiopatologia , Transtornos Cromossômicos/genética , Modelos Animais de Doenças , Epilepsia/genética , Deficiência Intelectual/genética , Camundongos , Esquizofrenia/genética , Convulsões/genética , Animais , Comportamento Animal/fisiologia , Peso Corporal/genética , Deleção Cromossômica , Cromossomos Humanos Par 15/genética , Eletroencefalografia , Feminino , Humanos , Masculino , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade
19.
Nature ; 505(7483): 361-6, 2014 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-24352232

RESUMO

In a small fraction of patients with schizophrenia or autism, alleles of copy-number variants (CNVs) in their genomes are probably the strongest factors contributing to the pathogenesis of the disease. These CNVs may provide an entry point for investigations into the mechanisms of brain function and dysfunction alike. They are not fully penetrant and offer an opportunity to study their effects separate from that of manifest disease. Here we show in an Icelandic sample that a few of the CNVs clearly alter fecundity (measured as the number of children by age 45). Furthermore, we use various tests of cognitive function to demonstrate that control subjects carrying the CNVs perform at a level that is between that of schizophrenia patients and population controls. The CNVs do not all affect the same cognitive domains, hence the cognitive deficits that drive or accompany the pathogenesis vary from one CNV to another. Controls carrying the chromosome 15q11.2 deletion between breakpoints 1 and 2 (15q11.2(BP1-BP2) deletion) have a history of dyslexia and dyscalculia, even after adjusting for IQ in the analysis, and the CNV only confers modest effects on other cognitive traits. The 15q11.2(BP1-BP2) deletion affects brain structure in a pattern consistent with both that observed during first-episode psychosis in schizophrenia and that of structural correlates in dyslexia.


Assuntos
Transtorno Autístico/genética , Cognição/fisiologia , Variações do Número de Cópias de DNA/genética , Predisposição Genética para Doença , Esquizofrenia/genética , Adolescente , Adulto , Idoso , Encéfalo/anormalidades , Encéfalo/anatomia & histologia , Encéfalo/metabolismo , Estudos de Casos e Controles , Deleção Cromossômica , Cromossomos Humanos/genética , Cromossomos Humanos Par 15/genética , Dislexia/genética , Feminino , Fertilidade/genética , Heterozigoto , Humanos , Islândia , Transtornos de Aprendizagem/genética , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Fenótipo , Adulto Jovem
20.
J Learn Disabil ; 47(6): 532-42, 2014 Nov-Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23456983

RESUMO

This article describes psychometric testing of an Icelandic adaptation of the Adult Reading History Questionnaire (ARHQ), designed to detect a history of reading difficulties indicative of dyslexia. Tested in a large and diverse sample of 2,187 adults, the Icelandic adaptation demonstrated internal consistency reliability (Cronbach's alpha = .92) and test-retest reliability (r = .93). Validity was established by comparing scores of adults who as children received ICD-10 diagnoses of specific reading disorder (F81.0; n = 419) to those of adults defined as nondyslexics (n = 679). ROC curve analysis resulted in an area under the curve of .92 (95% CI = .90, .93, p < .001) and a cutoff score of .43 with sensitivity of 84.5% and specificity of 83.7%. An exploratory factor analysis (n = 2,187) suggested three subscales, Dyslexia Symptoms, Current Reading, and Memory, the mean scores of which differed significantly among diagnosed dyslexics, relatives of dyslexics, and population controls. Our results support the applicability of the ARHQ in Icelandic as a self-report screening tool for adult dyslexia in Iceland.


Assuntos
Dislexia/diagnóstico , Psicometria/instrumentação , Leitura , Inquéritos e Questionários/normas , Adulto , Humanos , Islândia , Reprodutibilidade dos Testes
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA