People affected by depression may have genes associated with anxiety, worry and low mood, a study suggests.
Scientists analysed the DNA of over 300,000 people and found many genes linked to neuroticism – characterised by feelings of anxiety, worry and guilt. The genes are also linked to depression.
The findings help shed light on the causes of depression – which affects one in five people – and could provide information to help better diagnosis and treatment for individuals, scientists say.
Researchers analysed genetic information from a group of people aged from 39 to 73, whose levels of neuroticism had been measured by a personality questionnaire.
DNA analysis combined with the personality data uncovered 116 gene variations linked to neuroticism.
Researchers from the University of Edinburgh found that genes associated with neuroticism had some overlap with genes linked to a susceptibility to depression and some other psychiatric conditions.
More than half of the genetic variations associated with neuroticism are expressed in the brain.
Michelle Luciano, of the University of Edinburgh’s Centre for Cognitive Ageing and Cognitive Epidemiology (CCACE), who led the study, said: “This is the largest study of its kind in the area of personality. These discoveries promise paths to understand the mechanisms whereby some people become depressed, and of broader human differences in happiness. They are a resource for those seeking treatments for depression.”
Ian Deary, also of CCACE, who led the research team, said: “For millennia it has been recognised that people have a greater or lesser tendency to feel low, worry, and experience other negative emotions. We knew that a part of the explanation is genetic differences between people, but it’s been a mystery which genes are involved.
“These new results, from the very large UK Biobank sample, make a substantial contribution to solving that mystery by pointing to many specific places in the genome that are linked with neuroticism.”
The study used data in the UK Biobank, a major genetic study into the role of nature and nurture in health and disease.
The University of Edinburgh Centre for Cognitive Ageing and Cognitive Epidemiology receives funding from the Medical Research Council (MRC) and the Biotechnology and Biological Sciences Research Council.
UK Biobank was established by the Wellcome Trust, MRC, Department of Health, Scottish Government and the Northwest Regional Development Agency. It has had funding from the Welsh Assembly Government, British Heart Foundation and Diabetes UK. UK Biobank is hosted by the University of Manchester and supported by the NHS.