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1.
Acta Neuropsychiatr ; 36(2): 87-96, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36700449

RESUMO

The current small study utilised prospective data collection of patterns of prenatal alcohol and tobacco exposure (PAE and PTE) to examine associations with structural brain outcomes in 6-year-olds and served as a pilot to determine the value of prospective data describing community-level patterns of PAE and PTE in a non-clinical sample of children. Participants from the Safe Passage Study in pregnancy were approached when their child was ∼6 years old and completed structural brain magnetic resonance imaging to examine with archived PAE and PTE data (n = 51 children-mother dyads). Linear regression was used to conduct whole-brain structural analyses, with false-discovery rate (FDR) correction, to examine: (a) main effects of PAE, PTE and their interaction; and (b) predictive potential of data that reflect patterns of PAE and PTE (e.g. quantity, frequency and timing (QFT)). Associations between PAE, PTE and their interaction with brain structural measures demonstrated unique profiles of cortical and subcortical alterations that were distinct between PAE only, PTE only and their interactive effects. Analyses examining associations between patterns of PAE and PTE (e.g. QFT) were able to significantly detect brain alterations (that survived FDR correction) in this small non-clinical sample of children. These findings support the hypothesis that considering QFT and co-exposures is important for identifying brain alterations following PAE and/or PTE in a small group of young children. Current results demonstrate that teratogenic outcomes on brain structure differ as a function PAE, PTE or their co-exposures, as well as the pattern (QFT) or exposure.


Assuntos
Efeitos Tardios da Exposição Pré-Natal , Criança , Gravidez , Feminino , Humanos , Pré-Escolar , Projetos Piloto , África do Sul , Encéfalo/patologia , Imageamento por Ressonância Magnética
2.
J Hered ; 112(5): 447-451, 2021 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-34223905

RESUMO

Over 30 polymorphisms in the KIT Proto-Oncogene Receptor Tyrosine Kinase (KIT) gene have been implicated in white spotting patterns ranging from small areas to full dermal depigmentation in the horse. We performed a candidate-gene exon sequencing approach on KIT and MITF, 2 known causatives of white spotting patterns, within 2 families of horses of unknown white spotting. Family 1 (Fam1, N = 5) consisted of a Quarter Horse stallion and 4 offspring with white spotting pattern ranging from legs, lower ventral, and head regions with jagged borders, to almost complete white. The second family (Fam2, N = 7) consisted of 6 half-sibling American Paint Horse/Quarter Horse and their dam, demonstrating unpigmented limbs with belly spots and an extensive white patterning on the face. This approach resulted in 2 variants significantly associated with familial phenotypes, where Fam1 variant is an indel leading to a frameshift mutation, and Fam2 a non-synonymous SNP. We validated the variants within an unrelated population of horses (Fam2 variant, P = 0.00271944) as well as for protein functional impact with ExPASy, Protter, Phyre2, SMART, PROVEAN, SIFT, and I-TASSER, confirming the reported associations. Fam1 associated variant, deemed W31, alters the protein sequence, leading to an early stop codon truncating the normal amino acid sequence from 972 to just 115 amino acids. Fam2 associated variant, deemed W32, may have a subtle impact on receptor function or could be in linkage with a non-coding or regulatory change creating the mild spotting pattern observed in this family.


Assuntos
Cor de Cabelo , Proteínas Proto-Oncogênicas c-kit , Animais , Éxons , Ligação Genética , Cavalos/genética , Masculino , Fenótipo , Proteínas Proto-Oncogênicas c-kit/genética
4.
Addict Biol ; 25(6): e12830, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-31746534

RESUMO

While imaging studies have demonstrated volumetric differences in subcortical structures associated with dependence on various abused substances, findings to date have not been wholly consistent. Moreover, most studies have not compared brain morphology across those dependent on different substances of abuse to identify substance-specific and substance-general dependence effects. By pooling large multinational datasets from 33 imaging sites, this study examined subcortical surface morphology in 1628 nondependent controls and 2277 individuals with dependence on alcohol, nicotine, cocaine, methamphetamine, and/or cannabis. Subcortical structures were defined by FreeSurfer segmentation and converted to a mesh surface to extract two vertex-level metrics-the radial distance (RD) of the structure surface from a medial curve and the log of the Jacobian determinant (JD)-that, respectively, describe local thickness and surface area dilation/contraction. Mega-analyses were performed on measures of RD and JD to test for the main effect of substance dependence, controlling for age, sex, intracranial volume, and imaging site. Widespread differences between dependent users and nondependent controls were found across subcortical structures, driven primarily by users dependent on alcohol. Alcohol dependence was associated with localized lower RD and JD across most structures, with the strongest effects in the hippocampus, thalamus, putamen, and amygdala. Meanwhile, nicotine use was associated with greater RD and JD relative to nonsmokers in multiple regions, with the strongest effects in the bilateral hippocampus and right nucleus accumbens. By demonstrating subcortical morphological differences unique to alcohol and nicotine use, rather than dependence across all substances, results suggest substance-specific relationships with subcortical brain structures.


Assuntos
Encéfalo/diagnóstico por imagem , Neuroimagem , Transtornos Relacionados ao Uso de Substâncias/diagnóstico por imagem , Adolescente , Adulto , Cannabis/efeitos adversos , Cocaína/efeitos adversos , Etanol/efeitos adversos , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Metanfetamina/efeitos adversos , Nicotina/efeitos adversos , Adulto Jovem
5.
Am J Psychiatry ; 176(2): 119-128, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30336705

RESUMO

OBJECTIVE: Although lower brain volume has been routinely observed in individuals with substance dependence compared with nondependent control subjects, the brain regions exhibiting lower volume have not been consistent across studies. In addition, it is not clear whether a common set of regions are involved in substance dependence regardless of the substance used or whether some brain volume effects are substance specific. Resolution of these issues may contribute to the identification of clinically relevant imaging biomarkers. Using pooled data from 14 countries, the authors sought to identify general and substance-specific associations between dependence and regional brain volumes. METHOD: Brain structure was examined in a mega-analysis of previously published data pooled from 23 laboratories, including 3,240 individuals, 2,140 of whom had substance dependence on one of five substances: alcohol, nicotine, cocaine, methamphetamine, or cannabis. Subcortical volume and cortical thickness in regions defined by FreeSurfer were compared with nondependent control subjects when all sampled substance categories were combined, as well as separately, while controlling for age, sex, imaging site, and total intracranial volume. Because of extensive associations with alcohol dependence, a secondary contrast was also performed for dependence on all substances except alcohol. An optimized split-half strategy was used to assess the reliability of the findings. RESULTS: Lower volume or thickness was observed in many brain regions in individuals with substance dependence. The greatest effects were associated with alcohol use disorder. A set of affected regions related to dependence in general, regardless of the substance, included the insula and the medial orbitofrontal cortex. Furthermore, a support vector machine multivariate classification of regional brain volumes successfully classified individuals with substance dependence on alcohol or nicotine relative to nondependent control subjects. CONCLUSIONS: The results indicate that dependence on a range of different substances shares a common neural substrate and that differential patterns of regional volume could serve as useful biomarkers of dependence on alcohol and nicotine.


Assuntos
Córtex Cerebral/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Transtornos Relacionados ao Uso de Substâncias/diagnóstico por imagem , Adulto , Alcoolismo/diagnóstico por imagem , Transtornos Relacionados ao Uso de Anfetaminas/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Córtex Cerebral/patologia , Transtornos Relacionados ao Uso de Cocaína/diagnóstico por imagem , Feminino , Substância Cinzenta/patologia , Humanos , Masculino , Abuso de Maconha/diagnóstico por imagem , Metanfetamina , Pessoa de Meia-Idade , Tamanho do Órgão , Máquina de Vetores de Suporte , Tabagismo/diagnóstico por imagem , Adulto Jovem
6.
Sci Rep ; 8(1): 1982, 2018 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-29386528

RESUMO

The availability of genomic resources including linkage information for camelids has been very limited. Here, we describe the construction of a set of two radiation hybrid (RH) panels (5000RAD and 15000RAD) for the dromedary (Camelus dromedarius) as a permanent genetic resource for camel genome researchers worldwide. For the 5000RAD panel, a total of 245 female camel-hamster radiation hybrid clones were collected, of which 186 were screened with 44 custom designed marker loci distributed throughout camel genome. The overall mean retention frequency (RF) of the final set of 93 hybrids was 47.7%. For the 15000RAD panel, 238 male dromedary-hamster radiation hybrid clones were collected, of which 93 were tested using 44 PCR markers. The final set of 90 clones had a mean RF of 39.9%. This 15000RAD panel is an important high-resolution complement to the main 5000RAD panel and an indispensable tool for resolving complex genomic regions. This valuable genetic resource of dromedary RH panels is expected to be instrumental for constructing a high resolution camel genome map. Construction of the set of RH panels is essential step toward chromosome level reference quality genome assembly that is critical for advancing camelid genomics and the development of custom genomic tools.


Assuntos
Camelus/genética , Genoma , Mapeamento de Híbridos Radioativos , Animais , Cricetinae , DNA/genética , Feminino
7.
J Occup Environ Med ; 60(3): 248-257, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29252922

RESUMO

OBJECTIVE: To conduct a systematic literature review to identify social and occupational factors affecting the psychological wellbeing of healthcare workers involved in the severe acute respiratory syndrome (SARS) crisis. METHODS: Four literature databases were searched and data extracted from relevant papers. RESULTS: Eighteen thousand five papers were found and 22 included in the review. The psychological impact of SARS on employees appeared to be associated with occupational role; training/preparedness; high-risk work environments; quarantine; role-related stressors; perceived risk; social support; social rejection/isolation; and impact of SARS on personal or professional life. CONCLUSIONS: To minimize the psychological impact of future outbreaks of infectious diseases, healthcare workers should be prepared for the potential psychological impact; employers should encourage a supportive environment in the workplace and ensure that support is in place for those most at risk, for example, those with the most patient contact.


Assuntos
Surtos de Doenças , Pessoal de Saúde/psicologia , Exposição Ocupacional , Síndrome Respiratória Aguda Grave/epidemiologia , Síndrome Respiratória Aguda Grave/psicologia , Local de Trabalho/psicologia , Pessoal de Saúde/educação , Humanos , Saúde Ocupacional , Papel Profissional/psicologia , Distância Psicológica , Quarentena/psicologia , Isolamento Social , Apoio Social
9.
Behav Cogn Psychother ; 45(2): 156-169, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28098051

RESUMO

BACKGROUND: Cognitive-behavioural models of chronic fatigue syndrome (CFS) suggest that personality factors such as perfectionism and high moral standards may contribute to the development of CFS. AIMS: To investigate cognitive, behavioural and emotional processing risk factors for CFS. METHOD: CFS patients (n = 67) at a UK specialist clinic completed questionnaires about psychological characteristics both currently and retrospectively (6 months pre-CFS onset). Responses were compared with those of healthy individuals (n = 73) who rated their current characteristics. Forty-four relatives retrospectively rated the pre-morbid psychological characteristics of the CFS participants. RESULTS: CFS patients showed similar levels of current perfectionism to controls, though higher pre-morbid perfectionism. CFS patients showed greater self-sacrificial beliefs and more unhelpful beliefs about experiencing and expressing negative emotions, both currently but more markedly prior to onset. In the 6 months pre-illness onset, CFS patients showed more disruption to their primary goal and greater general stress than controls. Ratings of pre-morbid psychological characteristics by relatives were consistent with patients' self-reports. The extent of overinvestment in one goal was significantly associated with fatigue. CONCLUSIONS: Perfectionism, self-sacrificial tendencies, unhelpful beliefs about emotions, and perceived stress may be present to a greater extent pre-morbidly in CFS patients compared with healthy individuals.


Assuntos
Síndrome de Fadiga Crônica/etiologia , Síndrome de Fadiga Crônica/psicologia , Adulto , Estudos de Casos e Controles , Cognição , Terapia Cognitivo-Comportamental/métodos , Estudos Transversais , Cultura , Emoções , Feminino , Previsões , Humanos , Masculino , Pessoa de Meia-Idade , Perfeccionismo , Estudos Retrospectivos , Fatores de Risco , Autorrelato , Inquéritos e Questionários
10.
Int J Cancer ; 139(4): 784-92, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27037728

RESUMO

The common equine skin tumors known as sarcoids have been causally associated with infection by bovine papillomavirus (BPV). Additionally, there is evidence for host genetic susceptibility to sarcoids. We investigated the genetic basis of susceptibility to sarcoid tumors on a cohort of 82 affected horses and 270 controls genotyped on a genome-wide platform and two custom panels. A Genome Wide Association Study (GWAS) identified candidate regions on six chromosomes. Bayesian probability analysis of the same dataset verified only the regions on equine chromosomes (ECA) 20 and 22. Fine mapping using custom-produced SNP arrays for ECA20 and ECA22 regions identified two marker loci with high levels of significance: SNP BIEC2-530826 (map position 32,787,619) on ECA20 in an intron of the DQA1 gene in the Major Histocompatibility Complex (MHC) class II region (p = 4.6e-06), and SNP BIEC2-589604 (map position 25,951,536) on ECA22 in a 200 kb region containing four candidate genes: PROCR, EDEM2, EIF6 and MMP24 (p = 2.14e-06). The marker loci yielded odds ratios of 5.05 and 4.02 for ECA20 and ECA22, respectively. Associations between genetic MHC class II variants and papillomavirus-induced tumors have been reported for human papillomavirus and cottontail rabbit papillomavirus infections. This suggests a common mechanism for susceptibility to tumor progression that may involve subversion of the host immune response. This study also identified a genomic region other than MHC that influenced papillomavirus-induced tumor development in the studied population.


Assuntos
Predisposição Genética para Doença , Doenças dos Cavalos/epidemiologia , Doenças dos Cavalos/etiologia , Neoplasias/veterinária , Infecções por Papillomavirus/complicações , Alelos , Animais , Estudos de Casos e Controles , Mapeamento Cromossômico , Estudo de Associação Genômica Ampla , Cavalos , Desequilíbrio de Ligação , Razão de Chances , Infecções por Papillomavirus/virologia , Polimorfismo de Nucleotídeo Único , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/etiologia
11.
PLoS One ; 8(10): e78280, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24167615

RESUMO

Leopard complex spotting is a group of white spotting patterns in horses caused by an incompletely dominant gene (LP) where homozygotes (LP/LP) are also affected with congenital stationary night blindness. Previous studies implicated Transient Receptor Potential Cation Channel, Subfamily M, Member 1 (TRPM1) as the best candidate gene for both CSNB and LP. RNA-Seq data pinpointed a 1378 bp insertion in intron 1 of TRPM1 as the potential cause. This insertion, a long terminal repeat (LTR) of an endogenous retrovirus, was completely associated with LP, testing 511 horses (χ(2)=1022.00, p<<0.0005), and CSNB, testing 43 horses (χ(2)=43, p<<0.0005). The LTR was shown to disrupt TRPM1 transcription by premature poly-adenylation. Furthermore, while deleterious transposable element insertions should be quickly selected against the identification of this insertion in three ancient DNA samples suggests it has been maintained in the horse gene pool for at least 17,000 years. This study represents the first description of an LTR insertion being associated with both a pigmentation phenotype and an eye disorder.


Assuntos
Doenças dos Cavalos/genética , Mutagênese Insercional , Cegueira Noturna/genética , Cegueira Noturna/veterinária , Retroviridae/genética , Pigmentação da Pele/genética , Canais de Cátion TRPM/genética , Animais , Feminino , Cavalos , Masculino , Cegueira Noturna/metabolismo , Retroelementos , Canais de Cátion TRPM/metabolismo
12.
Anim Genet ; 44(6): 763-5, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23659293

RESUMO

Variants in the EDNRB, KIT, MITF, PAX3 and TRPM1 genes are known to cause white spotting phenotypes in horses, which can range from the common white markings up to completely white horses. In this study, we investigated these candidate genes in 169 horses with white spotting phenotypes not explained by the previously described variants. We identified a novel missense variant, PAX3:p.Pro32Arg, in Appaloosa horses with a splashed white phenotype in addition to their leopard complex spotting patterns. We also found three novel variants in the KIT gene. The splice site variant c.1346+1G>A occurred in a Swiss Warmblood horse with a pronounced depigmentation phenotype. The missense variant p.Tyr441Cys was present in several part-bred Arabians with sabino-like depigmentation phenotypes. Finally, we provide evidence suggesting that the common and widely distributed KIT:p.Arg682His variant has a very subtle white-increasing effect, which is much less pronounced than the effect of the other described KIT variants. We termed the new KIT variants W18-W20 to provide a simple and unambiguous nomenclature for future genetic testing applications.


Assuntos
Cabelo/fisiologia , Cavalos/genética , Fatores de Transcrição Box Pareados/genética , Fenótipo , Pigmentação/genética , Proteínas Proto-Oncogênicas c-kit/genética , Animais , Cavalos/fisiologia , Mutação de Sentido Incorreto/genética
13.
Am J Clin Nutr ; 96(3): 492-7, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22836029

RESUMO

BACKGROUND: Obesity is emerging as the most significant health concern of the 21st century. Although this is attributable in part to changes in our environment-including the increased prevalence of energy-dense food-it also appears that several lifestyle factors may increase our vulnerability to this calorie-rich landscape. Epidemiologic studies have begun to show links between adiposity and behaviors such as television watching, alcohol intake, and sleep deprivation. However, these studies leave unclear the direction of this association. In addition, studies that investigated the acute impact of these factors on food intake have reported a wide variety of effect sizes, from highly positive to slightly negative. OBJECTIVE: The purpose of this article was to provide a meta-analysis of the relation between lifestyle choices and increases in acute food intake. DESIGN: An initial search was performed on PubMed to collect articles relating television watching, sleep deprivation, and alcohol consumption to food intake. Only articles published before February 2012 were considered. Studies that took place in a controlled, laboratory setting with healthy individuals were included. Studies were analyzed by using 3 meta-analyses with random-effects models. In addition, a 1-factor ANOVA was run to discover any main effect of lifestyle. RESULTS: The 3 most prominent lifestyle factors-television watching, alcohol intake, and sleep deprivation-had significant short-term effects on food intake, with alcohol being more significant (Cohen's d = 1.03) than sleep deprivation (Cohen's d = 0.49) and television watching (Cohen's d = 0.2). CONCLUSIONS: Our results suggest that television watching, alcohol intake, and sleep deprivation are not merely correlated with obesity but likely contribute to it by encouraging excessive eating. Because these behaviors are all known to affect cognitive functions involved in reward saliency and inhibitory control, it may be that they represent common mechanisms through which this eating is facilitated.


Assuntos
Regulação do Apetite , Ingestão de Energia , Comportamento Alimentar , Estilo de Vida , Obesidade/etiologia , Consumo de Bebidas Alcoólicas/efeitos adversos , Humanos , Modelos Biológicos , Comportamento Sedentário , Privação do Sono/fisiopatologia , Televisão
14.
Br J Nutr ; 108(8): 1341-5, 2012 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-22214977

RESUMO

Smoking during pregnancy has been shown to be detrimental for the developing fetus. The effects of active and passive maternal smoking on umbilical cord serum levels of vitamin A and vitamin E were examined. Secondary measures included anthropometric parameters in the newborn. Maternal and umbilical cord serum levels of vitamins A and E were measured at delivery. The mothers were assigned to three groups: non-smoking (n 12); passive smoking (n 13); active smoking (n 18). Based on multivariate linear regressions, active smoking during pregnancy was associated with increased umbilical cord serum levels of vitamin A and vitamin E. While enhanced circulating levels of vitamin A in cord blood were also found in non-smoking mothers exposed to tobacco smoke during pregnancy, those of vitamin E were not influenced. Further, an inverse association between smoking behaviour during pregnancy and birth length was observed, with shortest length in active smokers followed by passive smoking mothers. Active and passive maternal smoking behaviour during pregnancy increases the fetal demand for antioxidant compounds in order to counteract the oxidative burden by cigarette smoke. Against this background, the observed increase in umbilical cord serum levels of vitamins A and E may subserve antioxidative processes in response to tobacco smoke-induced oxidative stress. This would reduce the availability of vitamins A and E for fetal maturation, which is critical inasmuch as both compounds are indispensable for the developing fetus. However, due to the cross-sectional nature of our observation, this line of reasoning definitely requires validation in cause-effect experiments in the future.


Assuntos
Antioxidantes/metabolismo , Sangue Fetal/metabolismo , Retardo do Crescimento Fetal/etiologia , Complicações na Gravidez , Fumar/efeitos adversos , Poluição por Fumaça de Tabaco/efeitos adversos , Vitaminas/sangue , Adulto , Antropometria , Estatura , Estudos Transversais , Feminino , Desenvolvimento Fetal , Retardo do Crescimento Fetal/sangue , Humanos , Recém-Nascido , Exposição Materna/efeitos adversos , Troca Materno-Fetal , Análise Multivariada , Estado Nutricional , Estresse Oxidativo , Gravidez , Produtos do Tabaco , Vitamina A/sangue , Vitamina A/metabolismo , Vitamina E/sangue , Vitamina E/metabolismo , Vitaminas/metabolismo
15.
J Psychosom Res ; 71(6): 411-5, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22118384

RESUMO

OBJECTIVE: In this paper we consider the role that acceptance plays in fatigue and physical and social functioning. We predicted that lack of acceptance would be positively correlated with fatigue and impairment in functioning; that there would be a significant relationship between perfectionism and acceptance; and cognitive behavioural therapy (CBT) would increase acceptance. METHODS: Two hundred and fifty nine patients with chronic fatigue syndrome (CFS) completed questionnaires measuring fatigue, physical functioning, work and social adjustment, lack of acceptance, perfectionism and depression. Ninety consecutive attenders received a course of CBT and completed further questionnaires at discharge and 3months post-treatment. Correlations and multiple hierarchical regressions were used to determine relationships between acceptance, perfectionism and clinical outcome variables. RESULTS: At baseline, lack of acceptance was the key factor associated with impaired physical functioning and work and social adjustment. Lack of acceptance and doubts about actions were associated with fatigue in a multiple regression analysis. At discharge and follow-up patients showed significantly increased acceptance, as well as reduced Concern over Mistakes, less fatigue and impairment of physical functioning, and improved work and social adjustment. CONCLUSION: This is the first study to our knowledge which shows a change in acceptance after CBT and a relationship between acceptance and perfectionism. Acceptance may be an important factor to consider within treatments for CFS.


Assuntos
Comportamento , Terapia Cognitivo-Comportamental , Síndrome de Fadiga Crônica/psicologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Emoções , Síndrome de Fadiga Crônica/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Inquéritos e Questionários , Resultado do Tratamento
16.
PLoS Genet ; 6(4): e1000909, 2010 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-20419149

RESUMO

Lavender Foal Syndrome (LFS) is a lethal inherited disease of horses with a suspected autosomal recessive mode of inheritance. LFS has been primarily diagnosed in a subgroup of the Arabian breed, the Egyptian Arabian horse. The condition is characterized by multiple neurological abnormalities and a dilute coat color. Candidate genes based on comparative phenotypes in mice and humans include the ras-associated protein RAB27a (RAB27A) and myosin Va (MYO5A). Here we report mapping of the locus responsible for LFS using a small set of 36 horses segregating for LFS. These horses were genotyped using a newly available single nucleotide polymorphism (SNP) chip containing 56,402 discriminatory elements. The whole genome scan identified an associated region containing these two functional candidate genes. Exon sequencing of the MYO5A gene from an affected foal revealed a single base deletion in exon 30 that changes the reading frame and introduces a premature stop codon. A PCR-based Restriction Fragment Length Polymorphism (PCR-RFLP) assay was designed and used to investigate the frequency of the mutant gene. All affected horses tested were homozygous for this mutation. Heterozygous carriers were detected in high frequency in families segregating for this trait, and the frequency of carriers in unrelated Egyptian Arabians was 10.3%. The mapping and discovery of the LFS mutation represents the first successful use of whole-genome SNP scanning in the horse for any trait. The RFLP assay can be used to assist breeders in avoiding carrier-to-carrier matings and thus in preventing the birth of affected foals.


Assuntos
Epilepsia/veterinária , Genoma , Doenças dos Cavalos/genética , Cavalos/genética , Miosinas/genética , Polimorfismo de Nucleotídeo Único , Animais , Sequência de Bases , Epilepsia/genética , Genótipo , Dados de Sequência Molecular , Síndrome
17.
Am J Clin Nutr ; 89(3): 755-65, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19176730

RESUMO

BACKGROUND: Disturbances in gastrointestinal hormones have been widely identified in persons with eating disorders (EDs) and have been implicated in their clinical pathologies. OBJECTIVE: The objective was to identify, critically examine, and summarize studies investigating the short-term response of gastrointestinal hormones to food in persons with an ED, including the subtypes anorexia nervosa and bulimia nervosa. DESIGN: A priori inclusion and exclusion criteria were set and included a procedure in which a test meal or glucose load was given and blood hormone concentrations measured. All studies included a healthy control group for comparison. The outcome variable was defined as the mean difference between fasting plasma hormone concentrations and the maximum postprandial peak or nadir. The difference in baseline values between groups was also examined. Pooled standardized mean differences were calculated and analyzed where possible. RESULTS: A total of 28 studies were identified, including sufficient studies to perform a meta-analysis for ghrelin, peptide YY, cholecystokinin, insulin, and pancreatic polypeptide. Persons with an ED had higher baseline concentrations of ghrelin (large effect), peptide YY (medium effect), and cholecystokinin (medium effect for ED, large effect for anorexia nervosa). The response of insulin to food was decreased in persons with an ED (medium effect). No further differences were found in the release of gut peptides to a standardized test meal. CONCLUSIONS: All of the studies had low power for the different subtypes of EDs. High heterogeneity among the studies was observed, and limitations are discussed. The findings suggest that the physiologic changes observed in patients with EDs are highly variable and subject to multiple confounding factors.


Assuntos
Transtornos da Alimentação e da Ingestão de Alimentos/metabolismo , Hormônios Gastrointestinais/metabolismo , Trato Gastrointestinal/metabolismo , Colecistocinina/sangue , Hormônios Gastrointestinais/sangue , Grelina/sangue , Humanos , Insulina/sangue , Polipeptídeo Pancreático/sangue , Peptídeo YY/sangue
18.
PLoS Genet ; 4(9): e1000195, 2008 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-18802473

RESUMO

Champagne coat color in horses is controlled by a single, autosomal-dominant gene (CH). The phenotype produced by this gene is valued by many horse breeders, but can be difficult to distinguish from the effect produced by the Cream coat color dilution gene (CR). Three sires and their families segregating for CH were tested by genome scanning with microsatellite markers. The CH gene was mapped within a 6 cM region on horse chromosome 14 (LOD = 11.74 for theta = 0.00). Four candidate genes were identified within the region, namely SPARC [Secreted protein, acidic, cysteine-rich (osteonectin)], SLC36A1 (Solute Carrier 36 family A1), SLC36A2 (Solute Carrier 36 family A2), and SLC36A3 (Solute Carrier 36 family A3). SLC36A3 was not expressed in skin tissue and therefore not considered further. The other three genes were sequenced in homozygotes for CH and homozygotes for the absence of the dilution allele (ch). SLC36A1 had a nucleotide substitution in exon 2 for horses with the champagne phenotype, which resulted in a transition from a threonine amino acid to an arginine amino acid (T63R). The association of the single nucleotide polymorphism (SNP) with the champagne dilution phenotype was complete, as determined by the presence of the nucleotide variant among all 85 horses with the champagne dilution phenotype and its absence among all 97 horses without the champagne phenotype. This is the first description of a phenotype associated with the SLC36A1 gene.


Assuntos
Sistemas de Transporte de Aminoácidos/genética , Éxons , Cor de Cabelo/genética , Cavalos/genética , Mutação de Sentido Incorreto , Simportadores/genética , Sequência de Aminoácidos , Sistemas de Transporte de Aminoácidos/metabolismo , Animais , Sequência de Bases , Feminino , Genes Dominantes , Ligação Genética , Cavalos/metabolismo , Masculino , Dados de Sequência Molecular , Fenótipo , Polimorfismo de Nucleotídeo Único , Alinhamento de Sequência , Simportadores/metabolismo
19.
PLoS Genet ; 3(11): e195, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17997609

RESUMO

White coat color has been a highly valued trait in horses for at least 2,000 years. Dominant white (W) is one of several known depigmentation phenotypes in horses. It shows considerable phenotypic variation, ranging from approximately 50% depigmented areas up to a completely white coat. In the horse, the four depigmentation phenotypes roan, sabino, tobiano, and dominant white were independently mapped to a chromosomal region on ECA 3 harboring the KIT gene. KIT plays an important role in melanoblast survival during embryonic development. We determined the sequence and genomic organization of the approximately 82 kb equine KIT gene. A mutation analysis of all 21 KIT exons in white Franches-Montagnes Horses revealed a nonsense mutation in exon 15 (c.2151C>G, p.Y717X). We analyzed the KIT exons in horses characterized as dominant white from other populations and found three additional candidate causative mutations. Three almost completely white Arabians carried a different nonsense mutation in exon 4 (c.706A>T, p.K236X). Six Camarillo White Horses had a missense mutation in exon 12 (c.1805C>T, p.A602V), and five white Thoroughbreds had yet another missense mutation in exon 13 (c.1960G>A, p.G654R). Our results indicate that the dominant white color in Franches-Montagnes Horses is caused by a nonsense mutation in the KIT gene and that multiple independent mutations within this gene appear to be responsible for dominant white in several other modern horse populations.


Assuntos
Alelos , Genes Dominantes , Heterogeneidade Genética , Cavalos/genética , Proteínas Proto-Oncogênicas c-kit/genética , Animais , Sequência de Bases , Western Blotting , Cruzamento , Citosina , Análise Mutacional de DNA , Genoma , Guanina , Dados de Sequência Molecular , Fenótipo , Polimorfismo Genético , Pele/metabolismo
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