Summary: A global analysis of nearly one million people has identified hundreds of genetic regions associated with socioeconomic status (SES), revealing a common genetic signal that links income, education, occupation and area-level deprivation. The study estimates that genetic differences explain about 9% of variation in SES, while the remaining variation is shaped by social, environmental and chance factors.
By examining brain MRI scans from more than 40,000 participants, researchers found that higher socioeconomic status is associated with fewer white matter hyperintensities—small areas of brain tissue change that are linked to cognitive decline and increased risk of dementia. Crucially, the findings indicate that SES is a modifiable influence on brain aging rather than a fixed genetic destiny.
Key facts
- Shared genetic signal: A substantial portion of the genetic effects related to income, education, occupation and deprivation overlaps across these measures.
- Brain health link: Greater socioeconomic status is associated with a lower burden of white matter lesions in the brain.
- Modifiable risk: Socioeconomic status acts as a changeable, causal factor in brain aging and cognitive maintenance.
Source: University of Edinburgh
Overview of the study
An international research team analysed genetic and social data from 947,466 adults to uncover how genetic variation relates to multiple measures of socioeconomic status: educational attainment, household income, occupational prestige and area-based social deprivation. The researchers used a multivariate genome-wide association study (GWAS) to capture genetic influences common across these SES measures and identified 554 genomic loci associated with the combined SES factor.
Approximately three quarters of the genetic effects linked to each socioeconomic measure overlapped, forming a unified genetic factor for SES. That factor explained about nine percent of the individual differences in socioeconomic position. The authors emphasise that most differences in income, education and occupation remain driven by environmental, policy and chance influences rather than genetics.
Brain imaging and causal analysis
To test whether SES influences brain structure, the team analysed MRI scans from a separate cohort of roughly 35,000–40,000 individuals. They focused on white matter hyperintensities (WMHs) expressed relative to intracranial volume, a widely used indicator linked to cognitive decline and dementia risk. Using genetic methods designed to infer causality, including Mendelian randomisation, the study found evidence that higher SES has a protective effect against the accumulation of WMHs.
Importantly, this protective relationship persisted even after accounting for individual differences in cognitive ability, suggesting that aspects of socioeconomic advantage contribute to healthier brain aging beyond the effects of cognition alone.
Implications
The findings demonstrate how genetic data can be used to disentangle the roles of heredity and environment, highlighting SES as a modifiable environmental factor that causally influences brain health in later life. While genetics contributes modestly to socioeconomic differences, social policies, living conditions, education and other environmental factors remain the primary drivers of unequal outcomes and present clear targets for intervention.
Researchers stress that the results do not imply brain health is genetically predetermined. Rather, genetic analyses helped reveal that improving socioeconomic conditions could play a meaningful role in reducing age-related brain changes and preserving cognitive function.
Research team and data sources
The study was led by researchers at the University of Edinburgh and involved collaborators from the Universities of Bristol, University College London, Modena (Italy), Vrije University (Netherlands) and Amsterdam University Medical Center. It used genetic and health data from large-scale resources including the UK Biobank and the Social Science Genetic Association Consortium.
About this brain aging research news
Author: Joanne Morrison ([email protected])
Source: University of Edinburgh
Contact: Joanne Morrison – University of Edinburgh
Image: Image credited to Neuroscience News
Original research: Open access. Title: “Deciphering the influence of socioeconomic status on brain structure: insights from Mendelian randomization” by David Hill et al., published in Molecular Psychiatry. DOI: 10.1038/s41380-025-03047-4
Abstract
Deciphering the influence of socioeconomic status on brain structure: insights from Mendelian randomization
Socioeconomic status (SES) affects physical and mental health, yet its relationship with brain structure has been less explored. This study used Mendelian randomisation to investigate SES effects on brain anatomy. First, a multivariate genome-wide association study combined educational attainment, household income, occupational prestige and area-based social deprivation in an effective sample of N = 947,466, identifying 554 loci associated with SES and isolating those common across the four traits. Second, using an independent imaging sample of approximately 35,000, the analysis provides evidence that higher SES is protective against white matter hyperintensities as a proportion of intracranial volume (WMHicv). Third, SES differences continued to show a protective effect on WMHicv independent of cognitive ability. Overall, the results support SES as a modifiable, causal factor in maintaining cognitive health into older age.