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Knowledge about the quality of care delivered to children with autism spectrum disorders (ASD) in relation to that recommended by clinical practice guidelines (CPGs) is limited. ASD care quality indicators were developed from CPGs and validated by experts, then used to assess the quality of care delivered by general practitioners (GPs) and pediatricians in Australia. Data were retrospectively collected from the medical records of 228 children (≤ 15 years) with ASD for 2012-2013. Overall quality of care was high, but with considerable variation among indicators, and between GPs and pediatricians-e.g., GPs were less likely to complete the assessment care bundle (61%; 95% CI 21-92). Findings highlight potential areas for improvement in the need for standardized criteria for diagnosis.
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Transtorno do Espectro Autista/terapia , Medicina Geral/normas , Qualidade da Assistência à Saúde , Austrália , Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/epidemiologia , Criança , Pré-Escolar , Feminino , Medicina Geral/estatística & dados numéricos , Humanos , Masculino , Prontuários Médicos/estatística & dados numéricosRESUMO
Precision measurements of the inverse-square law via experiments on short-range gravity provide sensitive tests of Lorentz symmetry. A combined analysis of data from experiments at the Huazhong University of Science and Technology and Indiana University sets simultaneous limits on all 22 coefficients for Lorentz violation correcting the Newton force law as the inverse sixth power of distance. Results are consistent with no effect at the level of 10^{-12} m^{4}.
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BACKGROUND: Patient satisfaction is an important outcome measure guiding quality improvement in the healthcare setting while the patient-centred care movement places increasing importance on patient engagement in clinical decision-making. However, the concept of patient satisfaction is not clearly defined, and beliefs of patients are not always evident in health surveys. Researchers rarely follow up on surveys to explore patient views and what they mean in greater depth. This study set out to examine perceptions of hospital care, through in-depth, qualitative data capture and as a result, to gather rich, patient-driven information on user experience and satisfaction in the Australian healthcare setting; and identify influencing factors. METHODS: Focus groups were undertaken in four St Vincent's Health Australia (SVHA) hospitals in 2017 where participants discussed responses to eight questions from the Press Ganey Patient Experience Survey. Thirty people who were inpatients at SVHA. RESULTS: Good communication and high-quality information at arrival and discharge were found to be important to patients. Communication breakdown was also evident, further exacerbated by a range of environmental factors such as sharing a room with others. Overall, patients' felt that while their spiritual needs were well-supported by the hospital staff at all SVHA hospitals, it was the clinical teams prioritised their emotional needs. Good communication and environments can improve patient experience and follow-up at home is vital. CONCLUSIONS: Patient-centred care needs careful planning with patients involved at entry and exit from hospital. Focused communication, environmental changes, attending to complaints, and clearer discharge strategies are recommended.
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Hospitais Privados , Hospitais Públicos , Preferência do Paciente , Satisfação do Paciente , Austrália , Feminino , Grupos Focais , Pesquisas sobre Atenção à Saúde , Humanos , MasculinoRESUMO
Short-range experiments testing the gravitational inverse-square law at the submillimeter scale offer uniquely sensitive probes of Lorentz invariance. A combined analysis of results from the short-range gravity experiments HUST-2015, HUST-2011, IU-2012, and IU-2002 permits the first independent measurements of the 14 nonrelativistic coefficients for Lorentz violation in the pure-gravity sector at the level of 10^{-9} m^{2}, improving by an order of magnitude the sensitivity to numerous types of Lorentz violation involving quadratic curvature derivatives and curvature couplings.
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INTRODUCTION: The close relationship between coagulation, thrombosis and cancer has long been established. Gynaecological cancers, in particular ovarian cancers, carry a high risk of thrombosis but coagulation activation is also thought to play a role in tumorigenesis and metastasis. In experimental animal models of metastasis, mice with a genetic procoagulant phenotype are prone to develop metastasis and anticoagulant therapy dramatically reduces pulmonary metastasis in these models. The aPC pathway is a key natural anticoagulant pathway, in addition to its role in venous thrombosis, dysregulation of this pathway is also thought to play a role in the pathogenesis of some cancers. No data exists in ovarian and endometrial cancers. AIM: The aim of this study is to determine the expression of key proteins of the activated protein C pathway in endometrial and ovarian malignant tumours compared to benign tumours and to assess their role in patient survival. MATERIALS AND METHODS: RNA was extracted from 78 (54 malignant and 24 benign) fresh frozen ovarian and endometrial tumours samples. Tumour biopsies were mRNA expression of endothelial protein C receptor (EPCR), protein S (PS), protein C (PC), thrombomodulin (TM), Factor V (FV) and VIII (FVIII) and PAR-1 and PAR-2 was measured using TaqMan Low Density Arrays. mRNA fold change relative to benign expression was determined using the 2 -delta delta Ct method with 18s as internal standard. All patients gave full and informed consent and the study had the approval of the hospital ethics committee. Total cell protein was extracted from ovarian tumour tissue. Enzyme-linked immunosorbent assay (ELISA) was used to measure protein plasma expression RESULTS: EPCR (P<0.001), protein S (P<0.0001) and Factor VIII (P<0.003) mRNA expression was significantly downregulated in malignant tumours compared with benign. Factor V and PAR-2 were significantly upregulated (P<0.001; P<0.004). Protein C was not consistently expressed. Reduced EPCR and TM protein expression was also observed in malignant tumours with increased plasma levels of Factor V. Reduced protein S and increased FV were associated with decreased survival. Plasma levels of Factor V were related to grade in the endometrial cancer group. PAR-2 mRNA expression was increased in ovarian tumours (P<0.001) however PAR-1 expression remained unchanged. CONCLUSIONS: Our results show reduced expression of key proteins associated with activation of protein C combined with increased expression in FV in gynaecological malignancies. These changes may contribute to local thrombin production and tumour progression and metastasis. Further work is required to determine the precise mechanisms involved.
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The three-wave migration hypothesis of Greenberg et al. has permeated the genetic literature on the peopling of the Americas. Greenberg et al. proposed that Na-Dene, Aleut-Eskimo and Amerind are language phyla which represent separate migrations from Asia to the Americas. We show that a unique allele at autosomal microsatellite locus D9S1120 is present in all sampled North and South American populations, including the Na-Dene and Aleut-Eskimo, and in related Western Beringian groups, at an average frequency of 31.7%. This allele was not observed in any sampled putative Asian source populations or in other worldwide populations. Neither selection nor admixture explains the distribution of this regionally specific marker. The simplest explanation for the ubiquity of this allele across the Americas is that the same founding population contributed a large fraction of ancestry to all modern Native American populations.
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Frequência do Gene , Genética Populacional , Indígenas Norte-Americanos/genética , Repetições de Microssatélites/genética , América , Emigração e Imigração , Geografia , Humanos , LinguísticaRESUMO
This paper investigates a mechanism of linguistic and genetic coevolution in Native Central and South America. This mechanism proposes that a process of population fissions, expansions into new territories, and isolation of ancestral and descendant groups will produce congruent language and gene trees. To evaluate this population fissions mechanism, we collected published mtDNA sequences for 1,381 individuals from 17 Native Central and South American populations. We then tested the hypothesis that three well-known language classifications also represented the genetic structure of these populations. We rejected the hypothesis for each language classification. Our tests revealed linguistic and genetic correspondence in several shallow branches common to each classification, but no linguistic and genetic correspondence in the deeper branches contained in two of the language classifications. We discuss the possible causes for the lack of congruence between linguistic and genetic structure in the region, and describe alternative mechanisms of linguistic and genetic correspondence and their predictions.
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Evolução Cultural , Variação Genética , Indígenas Centro-Americanos/genética , Indígenas Sul-Americanos/genética , Idioma , Filogenia , Dinâmica Populacional , Análise por Conglomerados , Biologia Computacional , DNA Mitocondrial/genética , Humanos , Modelos GenéticosRESUMO
Nonhuman primates offer unique opportunities to study the effects of genes, environments, and their interaction, on physiology and complex behavior. We examined genotype and early environment contributions to CNS function in a large sample of rhesus monkeys. In humans, length variation of the serotonin (5-HT) transporter (5-HTT) gene-linked polymorphic region (5-HTTLPR) that results in allelic variation in 5-HTT expression is associated with decreased serotonergic function and 5-HT-mediated psychopathology. We report that an analogous variation of the gene's regulatory region in monkeys interacts with early experience to affect central 5-HT functioning. Monkeys with deleterious early rearing experiences were differentiated by genotype in cerebrospinal fluid concentrations of the 5-HT metabolite, 5-hydroxyindoleacetic acid, while monkeys reared normally were not. These findings demonstrate an environment-dependent effect of the rh5-HTTLPR genotype on CNS 5-HT function and suggest nonhuman primates may provide an important avenue for investigating gene/environment interactions using candidate genes for physiological and behavioral traits.
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Encéfalo/fisiopatologia , Proteínas de Transporte/genética , Macaca mulatta/fisiologia , Glicoproteínas de Membrana/genética , Proteínas de Membrana Transportadoras , Repetições Minissatélites , Proteínas do Tecido Nervoso/genética , Regiões Promotoras Genéticas/genética , Meio Social , Estresse Psicológico/fisiopatologia , Alelos , Animais , Proteínas de Transporte/fisiologia , Coriocarcinoma/patologia , Feminino , Genes Reporter , Genótipo , Humanos , Ácido Hidroxi-Indolacético/líquido cefalorraquidiano , Luciferases/biossíntese , Macaca mulatta/genética , Macaca mulatta/psicologia , Masculino , Glicoproteínas de Membrana/fisiologia , Proteínas do Tecido Nervoso/fisiologia , Grupo Associado , Proteínas Recombinantes de Fusão/biossíntese , Serotonina/fisiologia , Proteínas da Membrana Plasmática de Transporte de Serotonina , Estresse Psicológico/líquido cefalorraquidiano , Estresse Psicológico/genética , Estresse Psicológico/psicologia , Mães Substitutas , Transcrição Gênica , Transfecção , Células Tumorais Cultivadas , Neoplasias Uterinas/patologiaRESUMO
OBJECTIVE: This study evaluated the performance of the CAGE questionnaire (a set of four questions about alcoholism) in an American Indian population. METHOD: We analyzed data from a cross-sectional study of 275 individuals (179 women) aged 21 years or older. Alcohol dependence was diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders, Third Edition-Revised (DSM-III-R), based on a detailed psychiatric interview using the Schedule for Affective Disorders and Schizophrenia-Lifetime Version. Accuracy of the CAGE questionnaire was quantified as sensitivity, specificity, likelihood ratios and the area under receiver operating characteristics (ROC) curves, using the DSM-III-R diagnosis as the reference. RESULTS: Of participants interviewed, 85% of men and 53% of women had a diagnosis of alcohol dependence by DSM-III-R. A CAGE score of > or = 2 had a sensitivity and specificity of 68% and 93%, respectively, in men and 62% and 79% in women, for the diagnosis of alcohol dependence. CAGE scores of 0, 1 and > or = 2 were associated with likelihood ratios of 0.3, 0.3 and 9.5, respectively, in men and 0.4, 0.7 and 1.5 in women. The area under the ROC curve was 81% for men and 75% for women. CONCLUSIONS: These findings suggest that the CAGE questionnaire is a valid screening method, in this population, for identifying people likely to have alcohol dependence.
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Alcoolismo/epidemiologia , Indígenas Norte-Americanos/estatística & dados numéricos , Inquéritos e Questionários , Adulto , Idoso , Alcoolismo/psicologia , Intervalos de Confiança , Feminino , Humanos , Indígenas Norte-Americanos/psicologia , Masculino , Pessoa de Meia-Idade , Razão de Chances , Escalas de Graduação Psiquiátrica/estatística & dados numéricos , Reprodutibilidade dos Testes , Detecção do Abuso de Substâncias/psicologia , Detecção do Abuso de Substâncias/estatística & dados numéricosRESUMO
Most of what is known about the structure and function of subunit a, of the ATP synthase, has come from the construction and isolation of mutations, and their analysis in the context of the ATP synthase complex. Three classes of mutants will be considered in this review. (1) Cys substitutions have been used for structural analysis of subunit a, and its interactions with subunit c. (2) Functional residues have been identified by extensive mutagenesis. These studies have included the identification of second-site suppressors within subunit a. (3) Disruptive mutations include deletions at both termini, internal deletions, and single amino acid insertions. The results of these studies, in conjunction with information about subunits b and c, can be incorporated into a model for the mechanism of proton translocation in the Escherichia coli ATP synthase.
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Escherichia coli/enzimologia , ATPases Translocadoras de Prótons/química , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Cisteína/genética , Proteínas de Membrana/química , Proteínas de Membrana/genética , Modelos Moleculares , Dados de Sequência Molecular , Mutação , ATPases Translocadoras de Prótons/genética , PrótonsRESUMO
Previous work from our laboratory has shown that cells of the immune system produce a growth hormone (GH) molecule similar to that produced by the pituitary. In the present study, using Southern analysis of RT-PCR products and sequencing of cloned cDNA molecules, we demonstrate that lymphoid cell lines utilize the same promoter and first exon as the pituitary somatotrope. To identify the cis-elements involved in transcriptional regulation of immune cell-derived GH, we have coupled rat GH promoter fragments to a luciferase reporter gene and transfected a monocyte cell line (P-388) by electroporation. The results suggest the presence of both positive (-299/-193 bp) and negative (-193/-107 bp) regulatory elements. The same constructs transfected in the pituitary cell line, GH3, in contrast to the monocyte cell line, showed a gradual decrease in luciferase expression. The overexpression of GHF-1 or GHF-2 resulted in a modest but significant reduction in rat GH promoter activity in the P-388 cell line. Taken together, the data suggest that immune cells utilize the same first exon and promoter sequence for the expression of monocyte GH as that reported for the expression of pituitary GH. Further, it appears that sequences between -299 and -107 bp are important in the regulation of the promoter where different transcription factors may be recruited to promote GH expression in a monocyte cell line.
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Regulação da Expressão Gênica , Hormônio do Crescimento/genética , Macrófagos/metabolismo , Monócitos/metabolismo , Adeno-Hipófise/metabolismo , Regiões Promotoras Genéticas , Animais , Comunicação Autócrina , Sequência de Bases , Southern Blotting , DNA Complementar/genética , Proteínas de Ligação a DNA/fisiologia , Eletroporação , Éxons/genética , Regulação Neoplásica da Expressão Gênica , Genes Reporter , Hormônio do Crescimento/biossíntese , Luciferases/biossíntese , Luciferases/genética , Camundongos , Dados de Sequência Molecular , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Especificidade de Órgãos , Neoplasias Hipofisárias/metabolismo , Neoplasias Hipofisárias/patologia , Ratos , Proteínas Recombinantes de Fusão/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição Pit-1 , Fatores de Transcrição/fisiologia , Transcrição Gênica , Células Tumorais CultivadasRESUMO
Individual genetic admixture estimates (IA) from European Americans (EAs) were computed in 7,996 members of the Gila River Indian Community (Arizona). Parental populations for the analysis were European Americans and full-heritage Pima Indians. A logistic regression was performed on 7,796 persons, to assess association of IA with type 2 diabetes. The odds ratio, comparing diabetes risk in full-heritage EAs with full-heritage Pima Indians, was 0.329 (95% confidence interval [CI] 0.225-0.482). Proportional-hazards analysis was performed on 5,482 persons who were nondiabetic at their first examination and 1,215 subjects who developed diabetes during the study. The hazard risk ratio for IA was 0.455 (95% CI 0.301-0.688). Nondiabetic persons had significantly more European IA. In nondiabetic Pimans, multivariate linear regressions of quantitative predictors of type 2 diabetes mellitus, including fasting plasma glucose, 2-h post-load plasma glucose, and body-mass index, showed significant inverse relations with IA when controlled for sex and age. These results illustrate the ongoing evolution of populations by the mechanism of gene flow and its effect on disease risk in the groups with admixture. When the two parental populations differ in disease prevalence, higher or lower risk is associated with admixture, depending on the origin of the admixed alleles and the relative magnitude of the disease prevalence in the parental populations. These data also illustrate the strong genetic components in type 2 diabetes and are consistent with one susceptibility locus common to obesity and diabetes.
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Glicemia/genética , Índice de Massa Corporal , Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença , Indígenas Norte-Americanos/genética , Obesidade/genética , Fatores Etários , Alelos , Glicemia/análise , Criança , Diabetes Mellitus Tipo 2/epidemiologia , Europa (Continente)/etnologia , Jejum , Feminino , Frequência do Gene/genética , Variação Genética/genética , Humanos , Modelos Logísticos , Masculino , Obesidade/epidemiologia , Razão de Chances , Prevalência , Modelos de Riscos Proporcionais , Fatores SexuaisRESUMO
Blue light regulates plant growth and development, and three photoreceptors, CRY1, CRY2, and NPH1, have been identified. The transduction pathways of these receptors are poorly understood. Transgenic plants containing aequorin have been used to dissect the involvement of these three receptors in the regulation of intracellular Ca2+. Pulses of blue light induce cytosolic Ca2+ transients lasting about 80 s in Arabidopsis and tobacco seedlings. Use of organelle-targeted aequorins shows that Ca2+ increases are limited to the cytoplasm. Blue light treatment of cry1, cry2, and nph1 mutants showed that NPH1, which regulates phototropism, is largely responsible for the Ca2+ transient. The spectral response of the Ca2+ transient is similar to that of phototropism, supporting NPH1 involvement. Furthermore, known interactions between red and blue light and between successive blue light pulses on phototropic sensitivity are mirrored in the blue light control of cytosolic Ca2+ in these seedlings. Our observations raise the possibility that physiological responses regulated by NPH1, such as phototropism, may be transduced through cytosolic Ca2+.
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Proteínas de Arabidopsis , Arabidopsis/metabolismo , Cálcio/metabolismo , Citosol/metabolismo , Proteínas de Drosophila , Proteínas do Olho , Luz , Nicotiana/metabolismo , Fosfoproteínas/efeitos da radiação , Células Fotorreceptoras de Invertebrados , Plantas Tóxicas , Equorina , Arabidopsis/citologia , Arabidopsis/genética , Arabidopsis/efeitos da radiação , Criptocromos , Citoplasma/metabolismo , Flavoproteínas/genética , Flavoproteínas/efeitos da radiação , Medições Luminescentes , Mutação , Fosfoproteínas/genética , Complexo de Proteínas do Centro de Reação Fotossintética/metabolismo , Complexo de Proteínas do Centro de Reação Fotossintética/efeitos da radiação , Fototropismo/efeitos da radiação , Proteínas Serina-Treonina Quinases , Receptores Acoplados a Proteínas G , Transdução de Sinais/fisiologia , Transdução de Sinais/efeitos da radiação , Nicotiana/citologia , Nicotiana/genética , Nicotiana/efeitos da radiaçãoRESUMO
The effect of human population subdivision on linkage disequilibrium has previously been studied for unlinked genes. However, no study has focused on closely linked polymorphisms or formally partitioned linkage disequilibrium within and among worldwide populations. With an emphasis on population subdivision, the goal of this paper is to investigate the causes of linkage disequilibrium in ALDH2, the gene that encodes aldehyde dehydrogenase 2. Haplotypes for 756 people from 17 populations across five continents were estimated by maximum-likelihood from genotypes at six closely linked ALDH2 nucleotide substitutions. Linkage disequilibrium was partitioned into three components: within populations, among populations within continents, and among continents. It was found that population subdivision among continents had a larger and more disparate effect on linkage disequilibrium than subdivision among local populations. Further, linkage disequilibrium did not increase with population divergence as predicted by a simple model. Rather, the patterns of linkage disequilibrium were complicated because of the interplay of a near absence of recombination, the linkage disequilibrium that existed prior to the divergence of modern humans, subsequent mutation, population subdivision, random genetic drift, and perhaps natural selection. These results suggest that simple models may not well predict patterns of linkage disequilibrium in human populations.
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Aldeído Desidrogenase/genética , Genética Populacional , Desequilíbrio de Ligação , Aldeído-Desidrogenase Mitocondrial , Alelos , Cromossomos Humanos Par 12 , Variação Genética , Haplótipos , Humanos , Modelos Genéticos , Modelos EstatísticosRESUMO
BACKGROUND: Heritable variation in brain monoaminergic activity has been suggested to lead to interindividual differences in vulnerability to alcoholism, and many other behavioral disorders. We evaluated if a functional Cys23Ser polymorphism in the 5-HT2C receptor gene, the principal serotonin receptor in the brain, contributes to variation in serotonin, norepinephrine and dopamine activity, as indexed by their major metabolite concentrations in cerebrospinal fluid (CSF). Genotype-monoamine metabolite concentration associations were subsequently correlated to risk for alcoholism. METHODS: The study sample consisted of unrelated Finnish males, including 214 alcoholic, violent offenders and 222 population controls who were interviewed using the Structured Clinical Interview for DSM-III-R, blind rated for psychiatric diagnoses and typed for the HTR2C Cys23Ser polymorphism. CSF concentrations of 5-hydroxyindoleacetic acid (5-HIAA), the major metabolite of serotonin, 3-methoxy-4-hydroxyphenylethyleneglycol (MHPG), the major metabolite of norepinephrine, and homovanillic acid (HVA), the major metabolite of dopamine were available from 195 individuals. RESULTS: The major finding in this study was that HTR2C CysSer23 significantly contributed to CSF MHPG concentrations (p = .012). Higher concentrations of CSF MHPG were observed both in alcoholic violent offenders and population controls with HTR2C Ser23 genotype. Despite the association of Cys23Ser to CSF MHPG, HTR2C genotype was not associated with alcoholism, nor with other psychiatric disorders present in this sample. CONCLUSIONS: We conclude that a functional HTR2C Cys23Ser polymorphism contributes to the interindividual genetic variation of CSF MHPG explaining 3% of the total variance. This finding suggests that 5-HT2C receptors are involved in the regulation of norepinephrine turnover in humans; however, HTR2C Cys23Ser does not appear to contribute to the risk of alcoholism, or its contribution to this complex and heterogenous disorder is too small to be detected by a sample of this size and structure.
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Monoaminas Biogênicas/líquido cefalorraquidiano , Genes/genética , Transtornos Mentais/diagnóstico , Polimorfismo Genético/genética , Alcoolismo/genética , Encéfalo/metabolismo , Dopamina/metabolismo , Genótipo , Ácido Homovanílico/líquido cefalorraquidiano , Humanos , Ácido Hidroxi-Indolacético/líquido cefalorraquidiano , Masculino , Metoxi-Hidroxifenilglicol/líquido cefalorraquidiano , Norepinefrina/metabolismo , Escalas de Graduação Psiquiátrica , Receptores de Serotonina/genética , Receptores de Serotonina/metabolismoRESUMO
Cysteine mutagenesis and surface labeling has been used to define more precisely the transmembrane spans of subunit a of the Escherichia coli ATP synthase. Regions of subunit a that are exposed to the periplasmic space have been identified by a new procedure, in which cells are incubated with polymyxin B nonapeptide (PMBN), an antibiotic derivative that partially permeabilizes the outer membrane of E. coli, along with a sulfhydryl reagent, 3-(N-maleimidylpropionyl) biocytin (MPB). This procedure permits reaction of sulfhydryl groups in the periplasmic space with MPB, but residues in the cytoplasm are not labeled. Using this procedure, residues 8, 27, 37, 127, 131, 230, 231, and 232 were labeled and so are thought to be exposed in the periplasm. Using inside-out membrane vesicles, residues near the end of transmembrane spans 1, 64, 67, 68, 69, and 70 and residues near the end of transmembrane spans 5, 260, 263, and 265 were labeled. Residues 62 and 257 were not labeled. None of these residues were labeled in PMBN-permeabilized cells. These results provide a more detailed view of the transmembrane spans of subunit a and also provide a simple and reliable technique for detection of periplasmic regions of inner membrane proteins in E. coli.
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Escherichia coli/enzimologia , Proteínas de Membrana/química , ATPases Translocadoras de Prótons/química , Sequência de Aminoácidos , Permeabilidade da Membrana Celular , Lisina/análogos & derivados , Maleimidas , Modelos Moleculares , Sondas Moleculares , Dados de Sequência Molecular , Periplasma/enzimologia , Polimixina B/análogos & derivados , Polimixina B/farmacologia , Conformação Proteica , Reagentes de SulfidrilaRESUMO
The high prevalence of rare genetic diseases in Finland has been attributed to a founder effect some 2,000 years ago. However, this hypothesis has not been supported from mtDNA sequence and autosomal microsatellite data which indicate high levels of gene diversity. Here we have identified genetic evidence for a population bottleneck by examining variable microsatellite loci on the nonrecombining portion of Y chromosomes from Finland and four populations from Europe and the Americas. Sequence data from segment I of the control region (HVS-1) of mtDNA (360 bases) and 20 autosomal dinucleotide repeat markers were also analyzed. Partitions of genetic variance within and between populations revealed significant levels of Y-chromosome differentiation between populations. Phylogenetic and diversity analyses revealed divergent Finnish Y-haplotype clades and significantly lower Y-haplotype diversity among Finns as compared to other populations. Surprisingly, Finnish Y-haplotype diversity was even lower than the Native American populations. These results provide support for the Finnish bottleneck hypothesis. Evidence for two separate founding Finnish Y-chromosome lineages was also observed from the Y-chromosome phylogeny. A limited number of closely related founding males may have contributed to the low number of paternal lineages in the Finnish population. In contrast, high levels of genetic diversity for mtDNA and autosomal STRs may be the result of sex-biased gene flow and recent immigration to urban areas from established internal isolates within Finland.
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DNA Mitocondrial/genética , Variação Genética , Genética Populacional , Cromossomo Y/genética , Sequência de Bases , Finlândia , Haplótipos , Humanos , Masculino , Repetições de Microssatélites , Modelos Genéticos , Dados de Sequência Molecular , FilogeniaRESUMO
The simultaneous analysis of closely linked nucleotide substitutions has recently become possible. However, it is not known whether the construction of molecular haplotypes will be a generally useful strategy for nuclear genes. Furthermore, whereas mobility-shift methods are widely used for the discovery of nucleotide substitutions, the yield of these methods has rarely been evaluated. This paper investigates these issues in non-coding regions of ALDH2, the gene that encodes aldehyde dehydrogenase 2 (ALDH2). Screening 20 Europeans, 20 native Americans, and 20 Asians by using restriction enzyme and single-strand conformation polymorphism (SSCP) analysis has revealed 16 variable sites. SSCP yields slightly fewer than the number of nucleotide substitutions predicted by the restriction enzyme digests. Estimates of nucleotide diversity are similar to those of other genes, suggesting that the pattern of polymorphism in ALDH2 offers a preview of what can be expected in many human nuclear genes. Eight of the variable sites discovered here and four sites discovered by others have been genotyped in 756 people from 17 populations across five continents. An expectation-maximization method has used to estimate haplotype states and frequencies. Only three haplotypes are common worldwide, and a fourth haplotype is common in, but private to, Asia. Although allele frequencies differ among sites, linkage disequilibrium is almost maximal across ALDH2. This suggests that haplotype construction at ALDH2 is particularly successful. The ALDH2 result, in conjunction with linkage disequilibrium results from other genes, indicates that haplotype construction will be a generally useful genomic strategy.
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Aldeído Desidrogenase/genética , Variação Genética , Aldeído-Desidrogenase Mitocondrial , Alelos , Enzimas de Restrição do DNA , Frequência do Gene , Genótipo , Haplótipos , Humanos , Desequilíbrio de Ligação , Polimorfismo Conformacional de Fita SimplesRESUMO
Association between Y chromosome haplotype variation and alcohol dependence and related personality traits was investigated in a large sample of psychiatrically diagnosed Finnish males. Haplotypes were constructed for 359 individuals using alleles at eight loci (seven microsatellite loci and a nucleotide substitution in the DYZ3 alphoid satellite locus). A cladogram linking the 102 observed haplotype configurations was constructed by using parsimony with a single-step mutation model. Then, a series of contingency tables nested according to the cladogram hierarchy were used to test for association between Y haplotype and alcohol dependence. Finally, using only alcohol-dependent subjects, we tested for association between Y haplotype and personality variables postulated to define subtypes of alcoholism-antisocial personality disorder, novelty seeking, harm avoidance, and reward dependence. Significant association with alcohol dependence was observed at three Y haplotype clades, with significance levels of P = 0.002, P = 0.020, and P = 0.010. Within alcohol-dependent subjects, no relationship was revealed between Y haplotype and antisocial personality disorder, novelty seeking, harm avoidance, or reward dependence. These results demonstrate, by using a fully objective association design, that differences among Y chromosomes contribute to variation in vulnerability to alcohol dependence. However, they do not demonstrate an association between Y haplotype and the personality variables thought to underlie the subtypes of alcoholism.
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Alcoolismo/genética , Alcoolismo/psicologia , Predisposição Genética para Doença , Modelos Genéticos , Personalidade/genética , Mutação Puntual , Cromossomo Y , Aprendizagem da Esquiva , Dependência Psicológica , Comportamento Exploratório , Finlândia , Marcadores Genéticos , Variação Genética , Haplótipos , Humanos , Masculino , Repetições de Microssatélites , Recompensa , Caracteres SexuaisRESUMO
Creutzfeldt-Jakob disease (CJD) belongs to a group of prion diseases that may be infectious, sporadic, or hereditary. The 200K point mutation in the PRNP gene is the most frequent cause of hereditary CJD, accounting for >70% of families with CJD worldwide. Prevalence of the 200K variant of familial CJD is especially high in Slovakia, Chile, and Italy, and among populations of Libyan and Tunisian Jews. To study ancestral origins of the 200K mutation-associated chromosomes, we selected microsatellite markers flanking the PRNP gene on chromosome 20p12-pter and an intragenic single-nucleotide polymorphism at the PRNP codon 129. Haplotypes were constructed for 62 CJD families originating from 11 world populations. The results show that Libyan, Tunisian, Italian, Chilean, and Spanish families share a major haplotype, suggesting that the 200K mutation may have originated from a single mutational event, perhaps in Spain, and spread to all these populations with Sephardic migrants expelled from Spain in the Middle Ages. Slovakian families and a family of Polish origin show another unique haplotype. The haplotypes in families from Germany, Sicily, Austria, and Japan are different from the Mediterranean or eastern European haplotypes. On the basis of this study, we conclude that founder effect and independent mutational events are responsible for the current geographic distribution of hereditary CJD associated with the 200K mutation.