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1.
Mol Phylogenet Evol ; 150: 106859, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32497831

RESUMO

Parapanteles Ashmead (Braconidae: Microgastrinae) is a medium-sized genus of microgastrine wasps that was erected over a century ago and lacks a unique synapomorphic character, and its monophyly has not been tested by any means. Parapanteles usually are parasitoids of large, unconcealed caterpillars (macrolepidoptera) and have been reared from an unusually large diversity of hosts for a relatively small microgastrine genus. We used Cytochrome Oxidase I sequences ("DNA barcodes") available for Parapanteles and other microgastrines to sample the generic diversity of described and undescribed species currently placed in Parapanteles, and then sequenced four additional genes for this subsample (wingless, elongation factor 1-alpha, ribosomal subunit 28s, and NADH dehydrogenase subunit 1). We constructed individual gene trees and concatenated Bayesian and maximum-likelihood phylogenies for this 5-gene subsample. In these phylogenies, most Parapanteles species formed a monophyletic clade within another genus, Dolichogenidea, while the remaining Parapanteles species were recovered polyphyletically within several other genera. The latter likely represent misidentified members of other morphologically similar genera. Species in the monophyletic clade containing most Parapanteles parasitized caterpillars from only five families - Erebidae (Arctiinae), Geometridae, Saturniidae, Notodontidae, and Crambidae. We do not make any formal taxonomic decisions here because we were not able to include representatives of type species for Parapanteles or other relevant genera, and because we feel such decisions should be reserved until a comprehensive morphological analysis of the boundaries of these genera is accomplished.


Assuntos
Himenópteros/classificação , Animais , Teorema de Bayes , Complexo IV da Cadeia de Transporte de Elétrons/classificação , Complexo IV da Cadeia de Transporte de Elétrons/genética , Himenópteros/genética , Proteínas de Insetos/classificação , Proteínas de Insetos/genética , NADH Desidrogenase/classificação , NADH Desidrogenase/genética , Filogenia , RNA Ribossômico 28S/classificação , RNA Ribossômico 28S/genética
2.
Mol Psychiatry ; 23(5): 1293-1302, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29112194

RESUMO

Despite moderate heritability, only one study has identified genome-wide significant loci for cannabis-related phenotypes. We conducted meta-analyses of genome-wide association study data on 2080 cannabis-dependent cases and 6435 cannabis-exposed controls of European descent. A cluster of correlated single-nucleotide polymorphisms (SNPs) in a novel region on chromosome 10 was genome-wide significant (lowest P=1.3E-8). Among the SNPs, rs1409568 showed enrichment for H3K4me1 and H3K427ac marks, suggesting its role as an enhancer in addiction-relevant brain regions, such as the dorsolateral prefrontal cortex and the angular and cingulate gyri. This SNP is also predicted to modify binding scores for several transcription factors. We found modest evidence for replication for rs1409568 in an independent cohort of African American (896 cases and 1591 controls; P=0.03) but not European American (EA; 781 cases and 1905 controls) participants. The combined meta-analysis (3757 cases and 9931 controls) indicated trend-level significance for rs1409568 (P=2.85E-7). No genome-wide significant loci emerged for cannabis dependence criterion count (n=8050). There was also evidence that the minor allele of rs1409568 was associated with a 2.1% increase in right hippocampal volume in an independent sample of 430 EA college students (fwe-P=0.008). The identification and characterization of genome-wide significant loci for cannabis dependence is among the first steps toward understanding the biological contributions to the etiology of this psychiatric disorder, which appears to be rising in some developed nations.


Assuntos
Cromossomos Humanos Par 10/genética , Abuso de Maconha/genética , Adulto , Negro ou Afro-Americano/genética , Alelos , Cannabis , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Frequência do Gene/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla/métodos , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , População Branca/genética , Adulto Jovem
3.
Transl Psychiatry ; 6: e761, 2016 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-27003187

RESUMO

Age at onset of alcohol dependence (AO-AD) is a defining feature of multiple drinking typologies. AO-AD is heritable and likely shares genetic liability with other aspects of alcohol consumption. We examine whether polygenic variation in AO-AD, based on a genome-wide association study (GWAS), was associated with AO-AD and other aspects of alcohol consumption in two independent samples. Genetic risk scores (GRS) were created based on AO-AD GWAS results from a discovery sample of 1788 regular drinkers from extended pedigrees from the Collaborative Study of the Genetics of Alcoholism (COGA). GRS were used to predict AO-AD, AD and Alcohol dependence symptom count (AD-SX), age at onset of intoxication (AO-I), as well as maxdrinks in regular drinking participants from two independent samples-the Study of Addictions: Genes and Environment (SAGE; n=2336) and an Australian sample (OZ-ALC; n=5816). GRS for AO-AD from COGA explained a modest but significant proportion of the variance in all alcohol-related phenotypes in SAGE. Despite including effect sizes associated with large numbers of single nucleotide polymorphisms (SNPs; >110 000), GRS explained, at most, 0.7% of the variance in these alcohol measures in this independent sample. In OZ-ALC, significant but even more modest associations were noted with variance estimates ranging from 0.03 to 0.16%. In conclusion, there is modest evidence that genetic variation in AO-AD is associated with liability to other aspects of alcohol involvement.


Assuntos
Alcoolismo/genética , Adulto , Idade de Início , Austrália , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Herança Multifatorial , Linhagem , Fenótipo , Estados Unidos , População Branca
4.
Zootaxa ; 3979(1): 1-98, 2015 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-26249935

RESUMO

A taxonomic review of the genus Hypomicrogaster Ashmead is presented with the redescription and redelimitation of the already named species Hypomicrogaster ecus Nixon, H. imitator (Ashmead), H. tydeus Nixon and H. zonaria (Say). The review also implies eleven new synonymies, and a new combination for the species H. areolaris (Blanchard). Also, the present revision identified 40 new Hypomicrogaster species: Hypomicrogaster aodous n. sp., H. aplebis n. sp., H. cernus n. sp., H. crocinus n. sp., H. daktulios n. sp., H. deltis n. sp., H. duo n. sp., H. epipagis n. sp., H. espera n. sp., H. evrys n. sp., H. guille n. sp., H. hektos n. sp., H. hupsos n. sp., H. ingensis n. sp., H. insolitus n. sp., H. inversalis n. sp., H. koinos n. sp., H. largus n. sp., H. laxus n. sp., H. linearis n. sp., H. lineatus n. sp., H. luisi n. sp., H. masoni n. sp., H. mesos n. sp., H. mikrosus n. sp., H. multus n. sp., H. pectinatus n. sp., H. plagios n. sp., H. pollex n. sp., H. rugosus n. sp., H. scindus n. sp., H. sicingens n. sp., H. sicpollex n. sp., H. sicscindus n. sp., H. siderion n. sp., H. spatulae n. sp., H. specialis n. sp., H. tantillus n. sp., H. tetra n. sp., H. zan n. sp. The Hypomicrogaster species are using as hosts 11 families of Lepidoptera, and 52 confirmed lepidopteran species feeding on 34 families of plants. Additionally, a fully illustrated key to all known described species of Hypomicrogaster is presented.


Assuntos
Himenópteros/anatomia & histologia , Himenópteros/classificação , Distribuição Animal , Animais , Feminino , Himenópteros/genética , Masculino , Especificidade da Espécie
5.
Obes Rev ; 16(4): 327-340, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25752329

RESUMO

Previously, a single nucleotide polymorphism (SNP), rs9939609, in the FTO gene showed a much stronger association with all-cause mortality than expected from its association with body mass index (BMI), body fat mass index (FMI) and waist circumference (WC). This finding implies that the SNP has strong pleiotropic effects on adiposity and adiposity-independent pathological pathways that leads to increased mortality. To investigate this further, we conducted a meta-analysis of similar data from 34 longitudinal studies including 169,551 adult Caucasians among whom 27,100 died during follow-up. Linear regression showed that the minor allele of the FTO SNP was associated with greater BMI (n = 169,551; 0.32 kg m(-2) ; 95% CI 0.28-0.32, P < 1 × 10(-32) ), WC (n = 152,631; 0.76 cm; 0.68-0.84, P < 1 × 10(-32) ) and FMI (n = 48,192; 0.17 kg m(-2) ; 0.13-0.22, P = 1.0 × 10(-13) ). Cox proportional hazard regression analyses for mortality showed that the hazards ratio (HR) for the minor allele of the FTO SNPs was 1.02 (1.00-1.04, P = 0.097), but the apparent excess risk was eliminated after adjustment for BMI and WC (HR: 1.00; 0.98-1.03, P = 0.662) and for FMI (HR: 1.00; 0.96-1.04, P = 0.932). In conclusion, this study does not support that the FTO SNP is associated with all-cause mortality independently of the adiposity phenotypes.


Assuntos
Adiposidade/genética , Obesidade/mortalidade , Polimorfismo de Nucleotídeo Único , Proteínas/genética , Dioxigenase FTO Dependente de alfa-Cetoglutarato , Índice de Massa Corporal , Predisposição Genética para Doença , Variação Genética , Estudo de Associação Genômica Ampla , Humanos , Obesidade/genética , Estudos Observacionais como Assunto , Circunferência da Cintura
6.
Mol Ecol Resour ; 13(2): 168-76, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23228011

RESUMO

Microgastrine wasps are among the most species-rich and numerous parasitoids of caterpillars (Lepidoptera). They are often host-specific and thus are extensively used in biological control efforts and figure prominently in trophic webs. However, their extraordinary diversity coupled with the occurrence of many cryptic species produces a significant taxonomic impediment. We present and release the results of 8 years (2004-2011) of DNA barcoding microgastrine wasps. Currently they are the best represented group of parasitoid Hymenoptera in the Barcode of Life Data System (BOLD), a massive barcode storage and analysis data management site for the International Barcoding of Life (iBOL) program. There are records from more than 20 000 specimens from 75 countries, including 50 genera (90% of the known total) and more than 1700 species (as indicated by Barcode Index Numbers and 2% MOTU). We briefly discuss the importance of this DNA data set and its collateral information for future research in: (1) discovery of cryptic species and description of new taxa; (2) estimating species numbers in biodiversity inventories; (3) clarification of generic boundaries; (4) biological control programmes; (5) molecular studies of host-parasitoid biology and ecology; (6) evaluation of shifts in species distribution and phenology; and (7) fostering collaboration at national, regional and world levels. The integration of DNA barcoding with traditional morphology-based taxonomy, host records, and other data has substantially improved the accuracy of microgastrine wasp identifications and will significantly accelerate further studies on this group of parasitoids.


Assuntos
Código de Barras de DNA Taxonômico , Filogenia , Vespas/classificação , Vespas/genética , Animais , Sequência de Bases , Dados de Sequência Molecular , Análise de Sequência de DNA
7.
Mol Psychiatry ; 18(11): 1218-24, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23089632

RESUMO

Several studies have identified genes associated with alcohol-use disorders (AUDs), but the variation in each of these genes explains only a small portion of the genetic vulnerability. The goal of the present study was to perform a genome-wide association study (GWAS) in extended families from the Collaborative Study on the Genetics of Alcoholism to identify novel genes affecting risk for alcohol dependence (AD). To maximize the power of the extended family design, we used a quantitative endophenotype, measured in all individuals: number of alcohol-dependence symptoms endorsed (symptom count (SC)). Secondary analyses were performed to determine if the single nucleotide polymorphisms (SNPs) associated with SC were also associated with the dichotomous phenotype, DSM-IV AD. This family-based GWAS identified SNPs in C15orf53 that are strongly associated with DSM-IV alcohol-dependence symptom counts (P=4.5 × 10(-8), inflation-corrected P=9.4 × 10(-7)). Results with DSM-IV AD in the regions of interest support our findings with SC, although the associations were less significant. Attempted replications of the most promising association results were conducted in two independent samples: nonoverlapping subjects from the Study of Addiction: Genes and Environment (SAGE) and the Australian Twin Family Study of AUDs (OZALC). Nominal association of C15orf53 with SC was observed in SAGE. The variant that showed strongest association with SC, rs12912251 and its highly correlated variants (D'=1, r(2) 0.95), have previously been associated with risk for bipolar disorder.


Assuntos
Alcoolismo/genética , Cromossomos Humanos Par 15/genética , Estudo de Associação Genômica Ampla , Fases de Leitura Aberta/genética , Avaliação de Sintomas , Alcoolismo/diagnóstico , Manual Diagnóstico e Estatístico de Transtornos Mentais , Endofenótipos , Feminino , Predisposição Genética para Doença/genética , Genótipo , Humanos , Masculino , Linhagem , Polimorfismo de Nucleotídeo Único
8.
Transl Psychiatry ; 2: e140, 2012 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-22806211

RESUMO

Addictions are serious and common psychiatric disorders, and are among the leading contributors to preventable death. This selective review outlines and highlights the need for a multi-method translational approach to genetic studies of these important conditions, including both licit (alcohol, nicotine) and illicit (cannabis, cocaine, opiates) drug addictions and the behavioral addiction of disordered gambling. First, we review existing knowledge from twin studies that indicates both the substantial heritability of substance-specific addictions and the genetic overlap across addiction to different substances. Next, we discuss the limited number of candidate genes which have shown consistent replication, and the implications of emerging genomewide association findings for the genetic architecture of addictions. Finally, we review the utility of extensions to existing methods such as novel phenotyping, including the use of endophenotypes, biomarkers and neuroimaging outcomes; emerging methods for identifying alternative sources of genetic variation and accompanying statistical methodologies to interpret them; the role of gene-environment interplay; and importantly, the potential role of genetic variation in suggesting new alternatives for treatment of addictions.


Assuntos
Predisposição Genética para Doença , Transtornos Relacionados ao Uso de Substâncias/genética , Biomarcadores , Manual Diagnóstico e Estatístico de Transtornos Mentais , Endofenótipos , Interação Gene-Ambiente , Estudos de Associação Genética , Variação Genética , Humanos , Farmacogenética , Transtornos Relacionados ao Uso de Substâncias/classificação , Transtornos Relacionados ao Uso de Substâncias/diagnóstico
9.
J Evol Biol ; 25(3): 532-46, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22268676

RESUMO

Host-parasite systems have been models for understanding the connection between shifts in resource use and diversification. Despite theoretical expectations, ambiguity remains regarding the frequency and importance of host switches as drivers of speciation in herbivorous insects and their parasitoids. We examine phylogenetic patterns with multiple genetic markers across three trophic levels using a diverse lineage of geometrid moths (Eois), specialist braconid parasitoids (Parapanteles) and plants in the genus Piper. Host-parasite associations are mapped onto phylogenies, and levels of cospeciation are assessed. We find nonrandom patterns of host use within both the moth and wasp phylogenies. The moth-plant associations in particular are characterized by small radiations of moths associated with unique host plants in the same geographic area (i.e. closely related moths using the same host plant species). We suggest a model of diversification that emphasizes an interplay of factors including host shifts, vicariance and adaptation to intraspecific variation within hosts.


Assuntos
Cadeia Alimentar , Interações Hospedeiro-Patógeno/genética , Mariposas/genética , Mariposas/parasitologia , Piper/genética , Árvores , Vespas/genética , Animais , Sequência de Bases , Teorema de Bayes , Biologia Computacional , Costa Rica , DNA Mitocondrial/genética , Equador , Evolução Molecular , Especiação Genética , Interações Hospedeiro-Patógeno/fisiologia , Larva/parasitologia , Larva/fisiologia , Modelos Genéticos , Dados de Sequência Molecular , Mariposas/classificação , Mariposas/fisiologia , Filogenia , Análise de Sequência de DNA , Vespas/fisiologia
10.
Diabetologia ; 52(11): 2359-2368, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19760390

RESUMO

AIMS/HYPOTHESIS: There has been much focus on the potential role of mitochondria in the aetiology of type 2 diabetes and the metabolic syndrome, and many case-control mitochondrial association studies have been undertaken for these conditions. We tested for a potential association between common mitochondrial variants and a number of quantitative traits related to type 2 diabetes in a large sample of >2,000 healthy Australian adolescent twins and their siblings, many of whom were measured on more than one occasion. METHODS: To the best of our knowledge, this is the first mitochondrial association study of quantitative traits undertaken using family data. The maternal inheritance pattern of mitochondria means established association methodologies are unsuitable for analysis of mitochondrial data in families. We present a methodology, implemented in the freely available program Sib-Pair for performing such an analysis. RESULTS: Despite our study having the power to detect variants with modest effects on these phenotypes, only one significant association was found after correction for multiple testing in any of four age groups. This was for mt14365 with triacylglycerol levels (unadjusted p = 0.0006). This association was not replicated in other age groups. CONCLUSIONS/INTERPRETATION: We find little evidence in our sample to suggest that common European mitochondrial variants contribute to variation in quantitative phenotypes related to diabetes. Only one variant showed a significant association in our sample, and this association will need to be replicated in a larger cohort. Such replication studies or future meta-analyses may reveal more subtle effects that could not be detected here because of limitations of sample size.


Assuntos
DNA Mitocondrial/genética , Diabetes Mellitus Tipo 2/genética , Síndrome Metabólica/genética , Adolescente , Glicemia/análise , Criança , Diabetes Mellitus Tipo 2/sangue , Família , Feminino , Geografia , Humanos , Lipídeos/sangue , Masculino , Síndrome Metabólica/sangue , Grupos Raciais , Irmãos
11.
J Evol Biol ; 22(8): 1762-9, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19555444

RESUMO

We provide the first phylogenetic evidence supporting complementary sex determination (CSD) as the ancestral mechanism for haplodiploidy in the Hymenoptera. It is currently not possible, however, to distinguish the evolutionary polarity of single locus (sl) CSD and multiple-locus (ml) CSD given the available data. In this light, we discuss the seemingly maladaptive hypothesis of ml-CSD ancestry, suggesting that collapse from ml-CSD to sl-CSD should remain a viable evolutionary hypothesis based on (i) likely weakening of frequency-dependent selection on sex alleles under ml-CSD and (ii) recent findings with respect to the evolutionary novelty of the complementary sex determiner gene in honeybees. Our findings help provide a phylogenetically informed blueprint for future sampling of sex determination mechanisms in the Hymenoptera, as they yield hypotheses for many unsampled or ambiguous taxa and highlight taxa whose further sampling will influence reconstruction of the evolutionary polarity of sex determination mechanisms in major clades.


Assuntos
Himenópteros/genética , Processos de Determinação Sexual , Animais , Feminino , Himenópteros/classificação , Masculino , Filogenia
12.
Chem Biol Interact ; 175(1-3): 343-5, 2008 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-18541229

RESUMO

We have undertaken a study on variations in cholinesterase (ChE) genes in relation to cardiovascular (CV) function and the metabolic syndrome. Peripheral and central nervous system control of cardiovascular (CV) function mediated through cholinergic pathways is critical in homeostatic maintenance of blood pressure and responsiveness to stress. For acetylcholinesterase (AChE; EC 3.1.1.7) our focus is to identify single nucleotide polymorphisms (SNPs) in the gene that are linked to cardiovascular function. For butyrylcholinesterase (BChE; EC 3.1.1.8) we examined whether BChE activity correlated with parameters of the metabolic syndrome and cardiovascular function. ChE can be found in whole blood enabling a characterization of biochemical phenotype in addition to correlating genotype with phenotypic physiologic responses. Analysis of enzymatic activity was determined spectrophotometrically in blood samples from twin and other subject registries. Correlation analysis revealed significant relationships between enzyme activity and certain CV endpoints. Linkage analysis with data from a dizygotic (DZ) twin set showed a suggestive linkage at the BChE locus, and statistical analysis revealed a high correlation between BChE activity and variables associated with cardiovascular risk and the metabolic syndrome. Pattern of within-pair twin correlations by zygosity and the ACE model-fitting findings suggest the major source of this variation (65%) is attributable to an additive genetic component. To date 19 SNPs have been identified by the re-sequencing of AChE including four nonsynonymous coding SNPs (cSNPs).


Assuntos
Acetilcolinesterase/genética , Butirilcolinesterase/genética , Farmacogenética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
Heredity (Edinb) ; 99(3): 288-94, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17551527

RESUMO

In the Hymenoptera, males develop as haploids from unfertilized eggs and females develop as diploids from fertilized eggs. In species with complementary sex determination (CSD), however, diploid males develop from zygotes that are homozygous at a highly polymorphic sex locus or loci. We investigated mating behavior and reproduction of diploid males of the parasitoid wasp Cotesia vestalis (C. plutellae), for which we recently demonstrated CSD. We show that the behavior of diploid males of C. vestalis is similar to that of haploid males, when measured as the proportion of males that display wing fanning, and the proportion of males that mount a female. Approximately 29% of diploid males sired daughters, showing their ability to produce viable sperm that can fertilize eggs. Females mated to diploid males produced all-male offspring more frequently (71%) than females mated to haploid males (27%). Daughter-producing females that had mated to diploid males produced more male-biased sex ratios than females mated to haploid males. All daughters of diploid males were triploid and sterile. Three triploid sons were also found among the offspring of diploid males. It has been suggested that this scenario, that is, diploid males mating with females and constraining them to the production of haploid sons, has a large negative impact on population growth rate and secondary sex ratio. Selection for adaptations to reduce diploid male production in natural populations is therefore likely to be strong. We discuss different scenarios that may reduce the sex determination load in C. vestalis.


Assuntos
Ploidias , Locos de Características Quantitativas/genética , Seleção Genética , Processos de Determinação Sexual , Vespas/genética , Animais , Cruzamentos Genéticos , Feminino , Masculino , Reprodução/genética
14.
Behav Genet ; 35(5): 509-24, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16184481

RESUMO

After ingestion of a standardized dose of ethanol, alcohol concentrations were assessed, over 3.5 hours from blood (six readings) and breath (10 readings) in a sample of 412 MZ and DZ twins who took part in an Alcohol Challenge Twin Study (ACTS). Nearly all participants were subsequently genotyped on two polymorphic SNPs in the ADH1B and ADH1C loci known to affect in vitro ADH activity. In the DZ pairs, 14 microsatellite markers covering a 20.5 cM region on chromosome 4 that includes the ADH gene family were assessed, Variation in the timed series of autocorrelated blood and breath alcohol readings was studied using a bivariate simplex design. The contribution of a quantitative trait locus (QTL) or QTL's linked to the ADH region was estimated via a mixture of likelihoods weighted by identity-by-descent probabilities. The effects of allelic substitution at the ADH1B and ADH1C loci were estimated in the means part of the model simultaneously with the effects sex and age. There was a major contribution to variance in alcohol metabolism due to a QTL which accounted for about 64% of the additive genetic covariation common to both blood and breath alcohol readings at the first time point. No effects of the ADH1B*47His or ADH1C*349Ile alleles on in vivo metabolism were observed, although these have been shown to have major effects in vitro. This implies that there is a major determinant of variation for in vivo alcohol metabolism in the ADH region that is not accounted for by these polymorphisms. Earlier analyses of these data suggested that alcohol metabolism is related to drinking behavior and imply that this QTL may be protective against alcohol dependence.


Assuntos
Álcool Desidrogenase/genética , Alcoolismo/genética , Cromossomos Humanos Par 14/genética , Etanol/sangue , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/genética , Adolescente , Adulto , Fatores Etários , Alcoolismo/sangue , Doenças em Gêmeos/genética , Feminino , Ligação Genética , Variação Genética , Haplótipos , Humanos , Masculino , Repetições de Microssatélites , Modelos Genéticos , Fatores Sexuais , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética
15.
Am J Med Genet B Neuropsychiatr Genet ; 124B(1): 113-23, 2004 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-14681925

RESUMO

The dopamine D4 receptor gene contains a polymorphic sequence consisting of a variable number of 48-base-pair (bp) repeats, and there have been a number of reports that this polymorphism is associated with variation in novelty seeking or in substance abuse and addictive behaviors. In this study we have assessed the linkage and association of DRD4 genotype with novelty seeking, alcohol use, and smoking in a sample of 377 dizygotic twin pairs and 15 single twins recruited from the Australian Twin Registry (ATR). We found no evidence of linkage or association of the DRD4 locus with any of the phenotypes. We made use of repeated measures for some phenotypes to increase power by multivariate genetic analysis, but allelic effects were still non-significant. Specifically, it has been suggested that the DRD4 7-repeat allele is associated with increased novelty seeking in males but we found no evidence for this, despite considerable power to do so. We conclude that DRD4 variation does not have an effect on use of alcohol and the problems that arise from it, on smoking, or on novelty seeking behavior.


Assuntos
Comportamento de Ingestão de Líquido , Variação Genética , Receptores de Dopamina D2/genética , Fumar , Austrália , Feminino , Frequência do Gene , Genótipo , Humanos , Desequilíbrio de Ligação , Masculino , Análise Multivariada , Fenótipo , Polimorfismo Genético , Receptores de Dopamina D4 , Gêmeos/genética , Gêmeos/estatística & dados numéricos , Gêmeos Dizigóticos/genética , Gêmeos Dizigóticos/estatística & dados numéricos , Gêmeos Monozigóticos/genética , Gêmeos Monozigóticos/estatística & dados numéricos
16.
Alcohol Clin Exp Res ; 25(9): 1257-63, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11584143

RESUMO

BACKGROUND: The significant association between alcohol dehydrogenase (ADH)-2 genotype and alcohol-dependence risk, demonstrated in both Asian and non-Asian populations, suggests a link between the metabolism of alcohol (ethanol) and individual differences in susceptibility to dependence. METHODS: We tested this hypothesis by following up on subjects who took part in the Alcohol Challenge Twin Study conducted in 1979-1981 and comparing the blood and breath alcohol results in that study between subjects who subsequently did or did not meet diagnostic criteria for lifetime alcohol dependence in 1992-1993. RESULTS: Subjects who met DSM-III-R criteria for lifetime alcohol dependence at follow-up had higher blood and breath alcohol values after alcohol challenge than never-dependent subjects. Multivariate analysis showed independent effects of susceptibility to alcohol dependence and smoking status on blood alcohol concentrations, whereas habitual alcohol intake at the time of the initial study had marginally significant effects. The risk of alcohol dependence was 2-fold higher in men and 3-fold higher in women with blood or breath alcohol concentrations in the highest quartile than in the lowest quartile. CONCLUSIONS: In view of this association and the known genetic influences on both alcohol pharmacokinetics and alcohol dependence, it is probable that part of the heritability of dependence is mediated by genes (other than the known ADH2 and ADH3 polymorphisms) affecting alcohol metabolism.


Assuntos
Alcoolismo/metabolismo , Etanol/farmacocinética , Adolescente , Adulto , Álcool Desidrogenase/genética , Alcoolismo/genética , Testes Respiratórios , Etanol/análise , Etanol/sangue , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Isoenzimas/genética , Masculino , Fatores de Risco , Fumar , Gêmeos
17.
Twin Res ; 4(2): 103-18, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11665331

RESUMO

Studies of alcoholism etiology often focus on genetic or psychosocial approaches, but not both. Greater understanding of the etiology of alcohol, tobacco and other addictions will come from integration of these research traditions. A research approach is outlined to test three models for the etiology of addictions--behavioral undercontrol, pharmacologic vulnerability, negative affect regulation--addressing key questions including (i) mediators of genetic effects, (ii) genotype-environment correlation effects, (iii) genotype x environment interaction effects, (iv) the developmental unfolding of genetic and environmental effects, (v) subtyping including identification of distinct trajectories of substance involvement, (vi) identification of individual genes that contribute to risk, and (vii) the consequences of excessive use. By using coordinated research designs, including prospective assessment of adolescent twins and their siblings and parents; of adult substance dependent and control twins and their MZ and DZ cotwins, the spouses of these pairs, and their adolescent offspring; and of regular families; by selecting for gene-mapping approaches sibships screened for extreme concordance or discordance on quantitative indices of substance use; and by using experimental (drug challenge) as well as survey approaches, a number of key questions concerning addiction etiology can be addressed. We discuss complementary strengths and weaknesses of different sampling strategies, as well as methods to implement such an integrated approach illustrated for the study of alcoholism etiology. A coordinated program of twin and family studies will allow a comprehensive dissection of the interplay of genetic and environmental risk-factors in the etiology of alcoholism and other addictions.


Assuntos
Alcoolismo/etiologia , Comportamento Aditivo/etiologia , Doenças em Gêmeos/etiologia , Alcoolismo/genética , Alcoolismo/psicologia , Comportamento Aditivo/genética , Comportamento Aditivo/psicologia , Família , Feminino , Humanos , Masculino , Modelos Genéticos , Modelos Psicológicos , Relações Pais-Filho , Projetos de Pesquisa , Fatores de Risco , Estudos de Amostragem , Cônjuges , Estudos em Gêmeos como Assunto/métodos
18.
Crit Rev Clin Lab Sci ; 38(4): 263-355, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11563810

RESUMO

Serum gamma-glutamyl transferase (GGT) has been widely used as an index of liver dysfunction and marker of alcohol intake. The last few years have seen improvements in these areas and advances in understanding of its physiological role in counteracting oxidative stress by breaking down extracellular glutathione and making its component amino acids available to the cells. Conditions that increase serum GGT, such as obstructive liver disease, high alcohol consumption, and use of enzyme-inducing drugs, lead to increased free radical production and the threat of glutathione depletion. However, the products of the GGT reaction may themselves lead to increased free radical production, particularly in the presence of iron. There have also been important advances in the definition of the associations between serum GGT and risk of coronary heart disease, Type 2 diabetes, and stroke. People with high serum GGT have higher mortality, partly because of the association between GGT and other risk factors and partly because GGT is an independent predictor of risk. This review aims to summarize the knowledge about GGT's clinical applications, to present information on its physiological roles, consider the results of epidemiological studies, and assess how far these separate areas can be combined into an integrated view.


Assuntos
gama-Glutamiltransferase , Alcoolismo/enzimologia , Animais , Biomarcadores , Doenças Cardiovasculares/enzimologia , Doenças Cardiovasculares/epidemiologia , Indução Enzimática , Expressão Gênica , Humanos , Hepatopatias/enzimologia , Mortalidade , Neoplasias/enzimologia , Estresse Oxidativo , Valores de Referência , Fatores de Risco , gama-Glutamiltransferase/deficiência , gama-Glutamiltransferase/genética , gama-Glutamiltransferase/fisiologia
19.
Alcohol Clin Exp Res ; 25(7): 1037-45, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11505030

RESUMO

BACKGROUND: Alcohol increases body iron stores. Alcohol and iron may increase oxidative stress and the risk of alcohol-related liver disease. The relationship between low or "safe" levels of alcohol use and indices of body iron stores, and the factors that affect the alcohol-iron relationship, have not been fully characterized. Other aspects of the biological response to alcohol use have been reported to depend on iron status. METHODS: We have measured serum iron, transferrin, and ferritin as indices of iron stores in 3375 adult twin subjects recruited through the Australian Twin Registry. Information on alcohol use and dependence and smoking was obtained from questionnaires and interviews. RESULTS: Serum iron and ferritin increased progressively across classes of alcohol intake. The effects of beer consumption were greater than those of wine or spirits. Ferritin concentration was significantly higher in subjects who had ever been alcohol dependent. There was no evidence of interactions between HFE genotype or body mass index and alcohol. Alcohol intake-adjusted carbohydrate-deficient transferrin was increased in women in the lowest quartile of ferritin results, whereas adjusted gamma-glutamyltransferase, aspartate aminotransferase, and alanine aminotransferase values were increased in subjects with high ferritin. CONCLUSIONS: Alcohol intake at low level increases ferritin and, by inference, body iron stores. This may be either beneficial or harmful, depending on circumstances. The response of biological markers of alcohol intake can be affected by body iron stores; this has implications for test sensitivity and specificity and for variation in biological responses to alcohol use.


Assuntos
Consumo de Bebidas Alcoólicas/sangue , Depressores do Sistema Nervoso Central/farmacologia , Etanol/farmacologia , Ferro/metabolismo , Adulto , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Biomarcadores , Índice de Massa Corporal , Feminino , Genótipo , Humanos , Ferro/sangue , Masculino , Polimorfismo Genético , Caracteres Sexuais , Fumar/metabolismo , Transferrina/análogos & derivados , Transferrina/metabolismo , gama-Glutamiltransferase/metabolismo
20.
Alcohol Clin Exp Res ; 25(5 Suppl ISBRA): 157S-163S, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11391066

RESUMO

This article represents the proceedings of a symposium at the 2000 ISBRA Meeting in Yokohama, Japan. The chairs were C. J. Peter Eriksson and Tatsushige Fukunaga. The presentations were (1) 4-Methylpyrazole as a tool in the investigation of the role of ADH in the actions of alcohol in humans, by Taisto Sarkola and C. J. Peter Eriksson; (2) ADH2 polymorphism and flushing in Asian populations, by Wei J. Chen, C. C. Chen, J. M. Ju, and Andrew T. A. Cheng; (3) Role of ADH3 genotypes in the acute effects of alcohol in a Finnish population, by Hidetaka Yamamoto, Kathrin Kohlenberg-Müller, and C. J. Peter Eriksson; (4) Clinical characteristics and disease course of alcoholics with different ADH2 genotypes, by Mitsuru Kimura, Masanobu Murayama, Sachio Matsushita, Haruo Kashima, and Susumu Higuchi; (5) ADH2 polymorphism, alcohol drinking, and birth defects, by Lucinda Carr, D. Viljoen, L. Brooke, T. Stewart, T. Foroud, J. Su, and Ting-Kai Li; and (6) ADH genotypes and alcohol use in Europeans, by John B. Whitfield.


Assuntos
Álcool Desidrogenase/genética , Consumo de Bebidas Alcoólicas/genética , Transtornos do Espectro Alcoólico Fetal/genética , Rubor/genética , Polimorfismo Genético/genética , Adulto , Aldeído Desidrogenase/genética , Aldeído-Desidrogenase Mitocondrial , Etnicidade/genética , Feminino , Genótipo , Humanos , Judeus/genética , Gravidez , População Branca/genética
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