Publications by authors named "Collier D"

The catechol-O-methyltransferase (COMT) val(158)met single nucleotide polymorphism (rs4680) has been shown to be associated with brain activation during a number of neurocognitive and emotional tasks. The present study evaluated genotypic associations with brain function during measurement of cognitive stability (prosaccades) and plasticity (antisaccades). A total of 36 healthy volunteers were genotyped for rs4680 and underwent functional magnetic resonance imaging (fMRI) at 1.

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Cigarette consumption and smoking cessation are influenced in part by genes. Personality traits have also been implicated in the aetiology of smoking. Neuroticism, a personality trait with a heritable component, correlates well with anxiety and depression, increasing the risk of being a smoker and decreasing the chance of smoking cessation.

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Recently, two common sequence variants on 9p21, tagged by rs10757278-G and rs10811661-T, were reported to be associated with coronary artery disease (CAD) and type 2 diabetes (T2D), respectively. We proceeded to further investigate the contributions of these variants to arterial diseases and T2D. Here we report that rs10757278-G is associated with, in addition to CAD, abdominal aortic aneurysm (AAA; odds ratio (OR) = 1.

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Cocaine addiction involves a number of medical, psychological and social problems. Understanding the genetic aetiology of this disorder will be essential for design of effective treatments. Dopamine-beta hydroxylase (DbH) catalyzes the conversion of dopamine to norepinephrine and could, therefore, have an influence on both cocaine action and the basal sensitivity of neurotransmitter systems to cocaine.

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There is growing evidence of partial aetiological overlap between schizophrenia and bipolar disorder (BP) from linkage analysis, genetic epidemiology and molecular genetics studies. In the present study we investigated whether individual polymorphisms or haplotypes of the DAO and G72(DAOA)/G30 genes, which have been previously implicated in schizophrenia, are also associated with bipolar disorder. For each gene, we genotyped 213 cases and 197 controls for SNPs previously associated with schizophrenia: rs2111902 (MDAAO-4), rs3918346 (MDAAO-5), rs3741775 (MDAAO-6) and rs3918347 (MDAAO-7) in DAO and rs746187 (M7), rs3916966 (M13), rs2391191 (M15) and rs3916972 (M25) in G72.

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The aim of this study was to investigate the relationship between polymorphisms in the PRODH and COMT genes and selected neurocognitive functions. Six SNPs in PRODH and two SNPs in COMT were genotyped in 167 first-episode schizophrenic families who had been assessed by a set of 14 neuropsychological tests. Neuropsychological measures were selected as quantitative traits for association analysis.

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This study examines the potential for a ventilatory drive, independent of mean PCO2, but depending instead on changes in PCO2 that occur during the respiratory cycle. This responsiveness is referred to here as "dynamic ventilatory sensitivity." The normal, spontaneous, respiratory oscillations in alveolar PCO2 have been modified with inspiratory pulses approximating alveolar PCO2 concentrations, both at sea level and at high altitude (5,000 m, 16,400 ft.

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We have genotyped 14,436 nonsynonymous SNPs (nsSNPs) and 897 major histocompatibility complex (MHC) tag SNPs from 1,000 independent cases of ankylosing spondylitis (AS), autoimmune thyroid disease (AITD), multiple sclerosis (MS) and breast cancer (BC). Comparing these data against a common control dataset derived from 1,500 randomly selected healthy British individuals, we report initial association and independent replication in a North American sample of two new loci related to ankylosing spondylitis, ARTS1 and IL23R, and confirmation of the previously reported association of AITD with TSHR and FCRL3. These findings, enabled in part by increased statistical power resulting from the expansion of the control reference group to include individuals from the other disease groups, highlight notable new possibilities for autoimmune regulation and suggest that IL23R may be a common susceptibility factor for the major 'seronegative' diseases.

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Objective: The objective was to provide an overall assessment of genetic linkage data of BMI and BMI-defined obesity using a nonparametric genome scan meta-analysis.

Research Methods And Procedures: We identified 37 published studies containing data on over 31,000 individuals from more than >10,000 families and obtained genome-wide logarithm of the odds (LOD) scores, non-parametric linkage (NPL) scores, or maximum likelihood scores (MLS). BMI was analyzed in a pooled set of all studies, as a subgroup of 10 studies that used BMI-defined obesity, and for subgroups ascertained through type 2 diabetes, hypertension, or subjects of European ancestry.

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Oxygen delivery (DO2) calculated from cardiac output, haematocrit (Hct) and arterial oxygen saturation (SaO2), has been obtained on six subjects at sea level (London) and after slow ascent to 5000 meters (Chamlang base camp) at rest and during mild exercise (25 watts and 50 watts). Haematocrit was increased in all six subjects at 5000 m and expressed as haemoglobin (Hb) rose from a mean (+/- standard error; SEM) of 13.8 +/- 0.

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Because of the role of dopamine in triggering migraine attacks, genes of the dopamine system are candidates for involvement in migraine. We examined three VNTR polymorphisms in the dopamine transporter, the 5'UTR VNTR, the intron 8 VNTR and the intron 14 VNTR, in a sample of 205 family trios. We used the transmission disequilibirium test (TDT) to examine the transmission of these three markers and their haplotypes to offspring affected by migraine.

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The G protein-coupled receptor kinase 3 gene (GRK3) is a candidate gene for cocaine addiction because it is involved in the regulation of several neurotransmitter receptors, including the response to dopaminergic agonists such as methamphetamine and cocaine. We hypothesized that genetic variants in the GRK3 gene might be associated with an increased risk of cocaine addiction. To test this, we genotyped three variants located in 5' untranslated and promoter regions of the gene in a sample of 711 cocaine users and 862 healthy control individuals from Sao Paulo, Brazil.

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Previous studies have suggested that catechol-O-methyltransferase (COMT), proline dehydrogenase (PRODH), and brain-derived neurotrophic factor (BDNF) genes are possible susceptibility genes for schizophrenia. We hypothesized that these genes are also associated with schizotypal traits, which are heritable and related to schizophrenia. We genotyped five single nucleotide polymorphism (SNPs) from the COMT, PRODH and BDNF genes, and performed a series of association analyses between alleles, genotypes or haplotypes, and quantitative schizotypal trait scores derived from the Schizotypal Personality Questionnaire (SPQ), in 465 Chinese healthy subjects.

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Genetic epidemiological twin studies have demonstrated a significant heritability for migraine, with > 60% of liability to migraine either with or without aura coming from additive genetic factors. Because of the essential role of serotonin in the pathophysiology and treatment of migraine, genes of the serotonin system are candidates for involvement in migraine. Consequently, we examined two functional VNTR polymorphisms in the serotonin transporter gene, the 5-HTTLPR and the intron 2 VNTR, in a sample of 212 family trios each with a proband with childhood migraine, 153 with migraine without aura (MoA) and 59 with migraine with aura (MA).

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Background: Previous studies have suggested that childhood eating and weight problems may be risk factors for eating disorders. Robust evidence is still lacking.

Aims: To investigate whether childhood eating and weight problems increase the risk of eating disorders in affected women compared to their unaffected sisters.

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Background: Wnt signaling has been implicated in schizophrenia from studies of gene expression in patients, from an understanding of the function of reported susceptibility genes and from experimental studies of psychoactive drugs. This diverse evidence suggests that wnt signaling genes, defined as pathway participants, modifiers or targets, are good candidates as susceptibility factors.

Methods: We performed a combined positional and candidate association screen by identifying known wnt signaling genes in regions linked to schizophrenia.

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Objective: As dopamine plays an important role in the pathophysiology of migraine and antimigraine drugs have an effect on the dopamine system, the objective of this study was to examine the dopamine D4 receptor gene for involvement in the cause of migraine.

Methods: We tested a VNTR-polymorphism in the dopamine D4 receptor gene, the exon 3 VNTR, in a sample of 190 family trios each with a proband with childhood migraine by using transmission disequilibrium test tests.

Results: We found a trend for transmission distortion of this marker in migraine, with the common seven-repeat allele of the VNTR transmitted 58 times and not transmitted 82 times (global likelihood ratio score (LRS) = 12.

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To examine whether there is an association between individual and family eating patterns during childhood and the likelihood of developing an eating disorder (ED) later in life. The sample comprised 261 eating disorder patients [33.5% [N=88] anorexia nervosa (AN), 47.

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Some neuropsychological abilities, particularly those affecting memory, attention and executive function, are impaired amongst both schizophrenic patients and their unaffected relatives, implying that these deficits are at least partly genetic in origin. However neuropsychological performance can be altered by medication, and has rarely been examined in first onset, drug naive patients. The objective of this study was to determine whether selected neurocognitive abilities are impaired in first-onset schizophrenic patients and their relatives compared to controls.

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Family and twin studies have revealed that genetic factors play a major role in psychiatric disorders, however, attempts to find susceptibility genes for these complex disorders have been largely unsuccessful. Therefore, new research strategies are required to tackle the complex interactions of genes, developmental, and environmental events. Here, we will address a behavioural domain concept that focuses on the genetics of behavioural domains relevant to both animal behaviour and across human psychiatric disorders.

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There is evidence suggesting that Dysbindin (DTNBP1) is a susceptibility gene for schizophrenia in Caucasian, Chinese, and Japanese populations. We sought to determine if dysbindin was associated with schizophrenia and its symptoms in a representative group of schizophrenic patients from a Community-Based Mental Health Service (CMHS) in Verona, Italy. A prevalence cohort of schizophrenic patients (n = 141) was assessed at baseline and then 3 and 6 years later.

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