Edinburgh
Xueyi Shen & Andrew McIntosh
Academic leads
Metabolic protein targets

Objectives
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Using advanced genetic tools and data from large biobanks like the UK Biobank and Generation Scotland, we will prioritise candidate proteins and metabolites with a likely causal role in SMI. We will then validate these targets using longitudinal cohort studies and perform multi-level analyses to understand how metabolic factors contribute to mental health, including the impact of polygenic risk scores on clinical outcomes. This work will also assess broader health effects through phenome-wide association studies (PheWAS).​
What we are doing
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1. Systematic genetic screening of metabolic proteins and metabolites
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We deploy large-scale Mendelian randomisation (MR) to test whether genetically predicted variation in circulating metabolic proteins or metabolites influences risk of SMI. We integrate:
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Proteomic QTL (pQTL) and metabolite QTL (metQTL) datasets
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Genome-wide association studies (GWAS) of SMI
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Large population cohorts including UK Biobank, ALSPAC and Generation Scotland
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This work is built upon our previous study interrogating causal relationship between metabolite abundance and Major Depression: see here.
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2. Multi-omic target validation or molecular targets that pass initial MR screening, we apply:
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Multi-trait fine-mapping
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Genetic co-localisation (eQTL/pQTL/chromatine accessibility/methQTL with SMI loci)
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Network and pathway enrichment analyses
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Drug target mapping
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This triangulation approach reduces false positives and increases confidence that prioritised proteins are biologically meaningful. This work has been published in Biological Psychiatry: see here.
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3. Trans-diagnostic and phenome-wide analyses
We evaluate whether inflammatory targets act:
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Across diagnostic categories (trans-diagnostic effects)
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In specific subgroups
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In relation to physical–mental health comorbidity
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Using MR-PheWAS approaches in large biobanks, we assess potential beneficial and adverse downstream consequences of modifying each target.
4. Diversity and global applicability
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Where possible, we incorporate GWAS and molQTL data from diverse ancestries, including African cohorts, to improve generalisability and mechanistic resolution.​​​
What we are planning to do
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Over the lifetime of ImmunoMIND we will:
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Expand screening to thousands of immune-related proteins and metabolites as datasets grow
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Integrate longitudinal -omic data and linked electronic health records to understand drug mechanism
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Provide validated target lists to the Therapeutic Personalisation platform for drug matching and repurposing
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Integrate recent advances in cell-type reference data to interrogate -omic associations with SMI that are specific to biological context.​
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Our ambition is to “funnel down” from hundreds of plausible inflammatory exposures to a small set (~5%) of genetically supported causal targets.
Find out more
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Key methodological foundations include:
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Two-sample Mendelian randomisation
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Genetic co-localisation and fine-mapping
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Transcriptomic and protein–protein interaction network analysis
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MR-PheWAS frameworks
Relevant prior work from our teams has demonstrated the feasibility of large-scale immune protein screening for psychiatric outcomes.
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Nisbet, L., …, Wray, N. R., McIntosh, A. M., & Shen, X. (2025). Integrating multi-omic summary data identifies candidate molecular mechanisms for Major Depression. Biol Psychiatry. https://doi.org/10.1016/j.biopsych.2025.11.024
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Shen, X. (2025). Limitations and Potential of Polygenic Risk Scores for Major Psychiatric Disorders. Biol Psychiatry, 98(6), 444-445. https://doi.org/10.1016/j.biopsych.2025.07.007
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Shen, X., …, Wray N. R., McIntosh, A. M. (2025). A methylome-wide association study of major depression with out-of-sample case-control classification and trans-ancestry comparison. Nat Ment Health, 3(10), 1152-1167. https://doi.org/10.1038/s44220-025-00486-4
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Shen, X., et al. (2025). Association between polygenic risk for Major Depression and brain structure in a mega-analysis of 50,975 participants across 11 studies. Mol Psychiatry. https://doi.org/10.1038/s41380-025-03136-4
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Xu, E. Y., ..., McIntosh, A. M., Shen, X., & Whalley, H. C. (2025). Epigenetic and Structural Brain Aging and Their Associations With Major Depressive Disorder. Biol Psychiatry Glob Open Sci, 5(6), 100577. https://doi.org/10.1016/j.bpsgos.2025.100577
Get involved
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