Publications by authors named "Nicholas Martin"

Objective: Alcohol use is common in older adults and linked to poor health and aging outcomes. Studies have demonstrated genetic and environmental contributions to the quantity of alcohol consumption in mid-to-late life, but less is known about whether these influences are moderated by sociodemographic factors such as age, sex, and educational attainment. This study sought to better understand sociodemographic trends in alcohol consumption across the second half of the life course and their underlying genetic and environmental influences.

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Antidepressants exhibit a considerable variation in efficacy, and increasing evidence suggests that individual genetics contribute to antidepressant treatment response. Here, we combined data on antidepressant non-response measured using rating scales for depressive symptoms, questionnaires of treatment effect, and data from electronic health records, to increase statistical power to detect genomic loci associated with non-response to antidepressants in a total sample of 135,471 individuals prescribed antidepressants (25,255 non-responders and 110,216 responders). We performed genome-wide association meta-analyses, genetic correlation analyses, leave-one-out polygenic prediction, and bioinformatics analyses for genetically informed drug prioritization.

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Macrophages are known to engulf small membrane fragments, or trogocytose, target cells and pathogens, rather than fully phagocytose them. However, little is known about what causes macrophages to choose trogocytosis versus phagocytosis. Here, we report that cortical tension of target cells is a key regulator of macrophage trogocytosis.

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Objectives: We examined associations between polygenic risk scores (PRS) for depression (PRS-MDD), psychosis (PRS-SCZ), bipolar disorders (PRS-BD) and neuroticism (PRS-NEU) and (i) help-seeking, and (ii) new onset cases of full-threshold mood or psychotic disorders in youth.

Methods: Help-seeking for mental health problems was assessed by self-report and mood and psychotic disorders were identified using the Composite International Diagnostic Interview. A principal component analysis of the four selected PRS identified two dimensions (BD-SCZ; MDD-NEU) that accounted for 69.

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Background: Premutation alleles of the FMR1 X-linked gene containing CGG repeat expansions ranging from 55 to 200 are associated with diverse late-onset neurological involvements, including most severe disorder termed Fragile X-associated Tremor/Ataxia Syndrome (FXTAS). It is intriguing that at least one-third of male, and a much lower than predicted from the X-linkage proportion of female carriers are free of this syndrome. This suggests the existence of secondary genetic factors modifying the risk of neurological involvements in these carriers.

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Background: Genetic vulnerability to mental disorders has been associated with coronavirus disease-19 (COVID-19) outcomes. We explored whether polygenic risk scores (PRSs) for several mental disorders predicted poorer clinical and psychological COVID-19 outcomes in people with pre-existing depression.

Methods: Data from three assessments of the Australian Genetics of Depression Study ( = 4405; 52.

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Article Synopsis
  • - This study is the first large-scale examination of rare copy number variants (CNVs) in anorexia nervosa (AN), involving data from 7,414 AN cases and 5,044 controls to explore their potential genetic links to the disorder.
  • - The researchers investigated both well-known syndromic CNVs and those associated with other diseases but found no significant links between these variants and AN; however, they identified 21 potential CNV regions that may play a role in AN risk, particularly in areas related to metabolic and neurodevelopmental factors.
  • - Ultimately, the findings suggest that rare CNVs have a limited impact on the development of AN, aligning it with other psychiatric disorders like bipolar disorder, and indicate that
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Background: It is well established that there is a substantial genetic component to eating disorders (EDs). Polygenic risk scores (PRSs) can be used to quantify cumulative genetic risk for a trait at an individual level. Recent studies suggest PRSs for anorexia nervosa (AN) may also predict risk for other disordered eating behaviors, but no study has examined if PRS for AN can predict disordered eating as a global continuous measure.

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  • Subcortical brain structures play a crucial role in various developmental and psychiatric disorders, and a study analyzed brain volumes in 74,898 individuals, identifying 254 genetic loci linked to these volumes, which accounted for up to 35% of variation.
  • The research included exploring gene expression in specific neural cell types, focusing on genes involved in intracellular signaling and processes related to brain aging.
  • The findings suggest that certain genetic variants not only influence brain volume but also have potential causal links to conditions like Parkinson’s disease and ADHD, highlighting the genetic basis for risks associated with neuropsychiatric disorders.
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  • Scientists studied how certain genes affect height and body mass index (BMI) by looking at families with siblings.
  • They found that links between genes and these traits could be seen both in family studies and in studies that look at a lot of DNA variations (called SNPs).
  • They discovered that there are still many genetic factors influencing height and BMI that haven't been identified yet, showing that genetics is really complex and involves many genes working together.
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  • Subcortical brain structures play a crucial role in various disorders, and a study analyzed the genetic basis of brain volumes in nearly 75,000 individuals of European ancestry, revealing 254 loci linked to these volumes.
  • The research identified significant gene expression in neural cells, relating to brain aging and signaling, and found that polygenic scores could predict brain volumes across different ancestries.
  • The study highlights genetic connections between brain volumes and conditions like Parkinson's disease and ADHD, suggesting specific gene expression patterns could be involved in neuropsychiatric disorders.
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  • - The study aimed to explore the genetic basis of major depressive disorder by analyzing symptoms across various clinical and community cohorts, acknowledging challenges like sample size differences and missing data patterns.
  • - Researchers performed genome-wide association studies using data from both diagnosed and undiagnosed participants, fitting models to understand the relationships between different depressive symptoms.
  • - Findings emphasized the relevance of symptom directionality (e.g., hypersomnia vs. insomnia) and the necessity of considering study design when analyzing genetic data related to depression.
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Melancholia has been proposed as a qualitatively distinct depressive subtype associated with a characteristic symptom profile (psychomotor retardation, profound anhedonia) and a better response to biological therapies. Existing work has suggested that individuals with melancholia are blunted in their display of positive emotions and differ in their neural response to emotionally evocative stimuli. Here, we unify these brain and behavioural findings amongst a carefully phenotyped group of seventy depressed participants, drawn from an established Australian database (the Australian Genetics of Depression Study) and further enriched for melancholia (high ratings of psychomotor retardation and anhedonia).

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Importance: It is unknown whether germline genetic factors influence in situ melanoma risk differently than invasive melanoma risk.

Objective: To determine whether differences in risk of in situ melanoma and invasive melanoma are heritable.

Design, Setting, And Participants: Three genome-wide association study meta-analyses were conducted of in situ melanoma vs controls, invasive melanoma vs controls, and in situ vs invasive melanoma (case-case) using 4 population-based genetic cohorts: the UK Biobank, the FinnGen cohort, the QSkin Sun and Health Study, and the Queensland Study of Melanoma: Environmental and Genetic Associations (Q-MEGA).

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  • Antidepressant effectiveness varies significantly among individuals, with genetics playing a role in how people respond to treatment.
  • A study analyzing data from 135,471 patients identified two new genetic locations (loci) linked to antidepressant non-response and confirmed the ability to predict treatment response using genetic information.
  • The research also explored potential new drug options that could help individuals who don't respond to traditional first-line antidepressants, highlighting the importance of larger sample studies for discovering relevant genetic factors.
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Unlabelled: The emergence and spread of chloroquine-resistant have necessitated the assessment of alternative blood schizonticidal drugs. In Vietnam, chloroquine-resistant malaria has been reported. In an open-label, single-arm trial, the safety, tolerability, and efficacy of pyronaridine-artesunate (Pyramax, PA) was evaluated in Dak Nong province, Vietnam.

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Dyslexia is a learning difficulty with neurodevelopmental origins, manifesting as reduced accuracy and speed in reading and spelling. It is substantially heritable and frequently co-occurs with other neurodevelopmental conditions, particularly attention deficit-hyperactivity disorder (ADHD). Here, we investigate the genetic structure underlying dyslexia and a range of psychiatric traits using results from genome-wide association studies of dyslexia, ADHD, autism, anorexia nervosa, anxiety, bipolar disorder, major depressive disorder, obsessive compulsive disorder, schizophrenia, and Tourette syndrome.

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  • * A genome-wide association meta-analysis of nearly 122,000 ANX cases revealed 58 significant genetic variants and 66 related genes, with many of these findings replicated in a larger independent sample.
  • * The findings indicate a substantial genetic overlap between ANX and other conditions like depression, emphasizing GABAergic signaling as a key mechanism, thereby enhancing our understanding of the genetic basis of ANX for future research.
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  • Scientists looked at the timing of when girls start their periods (called menarche) and how it can affect their health later in life.
  • They studied about 800,000 women and found over a thousand genetic signals that influence when menstruation starts.
  • Some women have a much higher chance of starting their periods too early or too late based on their genetic makeup, suggesting that genes play a big role in this process!
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Patterns of association with externalizing and internalizing features differ across heroin use and prescription opioid misuse (POM). The present study examined whether heroin use and POM display differential etiologic overlap with symptoms of conduct disorder (CD), adult antisocial behavior (AAB), and major depressive episodes (MDEs), how aggregating heroin use and POM into a single phenotype may bias results, and explored potential sex differences. Seven thousand one hundred and sixty-four individual twins from the Australian Twin Registry (ATR; 59.

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  • Individual sensitivity to environmental exposures is influenced by genetics, showing that different genetic makeups can lead to varying reactions to the same environment.
  • A large meta-analysis was conducted using data from nearly 22,000 monozygotic twins to explore genetic influences on seven psychiatric and neurodevelopmental traits.
  • The study found 13 significant genetic associations related to factors like stress-reactivity, growth factors, and catecholamine uptake, highlighting the potential role of genetics in understanding environmental sensitivity.
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  • Obsessive-compulsive disorder (OCD) affects about 1% of people and has a strong genetic component, but previous studies have not fully explained its genetic causes or biological mechanisms.
  • A large genome-wide association study (GWAS) analyzed data from over 53,000 OCD cases and over 2 million control participants, identifying 30 significant genetic markers related to OCD and suggesting a 6.7% heritability from SNPs.
  • The research also found 249 candidate risk genes linked to OCD, particularly in specific brain regions, and showed genetic correlations with various psychiatric disorders, laying the groundwork for further studies and potential treatments.
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  • PTSD genetics have been difficult to study compared to other psychiatric disorders, limiting our biological understanding of the condition.
  • A large-scale meta-analysis involving over 1.2 million individuals identified 95 genome-wide significant loci, with 80 being new discoveries related to PTSD.
  • Researchers identified 43 potential causal genes linked to neurotransmitter activity, developmental processes, synaptic function, and immune regulation, enhancing our knowledge of the neurobiological systems involved in PTSD.
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Introduction: Major depression (MD) is more common amongst women than men, and MD episodes have been associated with fluctuations in reproductive hormones amongst women. To investigate biological underpinnings of heterogeneity in MD, the associations between depression, stratified by sex and including perinatal depression (PND), and blood biomarkers, using UK Biobank (UKB) data, were evaluated, and extended to include the association of depression with biomarker polygenic scores (PGS), generated as proxy for each biomarker.

Method: Using female ( = 39,761) and male ( = 38,821) UKB participants, lifetime MD and PND were tested for association with 28 blood biomarkers.

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