Researchers have discovered a genetic link between depression and heart disease that could help to find new drugs to target both conditions.

A team of scientists at Tampere University in Finland identified a “gene module” consisting of 256 functionally related, co-expressed genes that contribute to the development of both diseases. The full findings of the study were published in the journal Frontiers in Psychiatry.

This gene module–a group of genes with similar expression patterns across different conditions–provides new biomarkers for depression and cardiovascular disease.

For the study, the researchers studied gene expression data in the blood of 899 women and men between 34 and 49 years old. They were all participants in the Young Finns longitudinal study, which examined cardiovascular risk factors from childhood to adulthood.

In 2011, the researchers running the Young Finns study tested the participants for symptoms of depression with a survey called Beck’s depression inventory. They also tested the participants for the risk of developing heart disease.

In the new study, the team further analyzed these data. They looked at the gene expression profile in the blood of people with depression and heart disease and found one gene module whose expression at levels higher or lower than average puts people at greater risk of both diseases.

“The top three genes from this gene module are known to be associated with neurodegenerative diseases, bipolar disorder, and depression. Now we have shown that they are associated with poor cardiovascular health as well,” said lead author Binisha Mishra, a postdoctoral researcher.

These three genes–that belong to the gene module–are involved in inflammation that is linked to both depression and cardiovascular disease. This helps to explain why both diseases often occur together.

Blood pressure
Stock photo of a man getting his blood pressure tested. Scientists have discovered a genetic link between heart disease and depression.

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“We can use the genes in this module as biomarkers for depression and cardiovascular disease. Ultimately, these biomarkers may facilitate the development of dual-purpose preventative strategies for both the diseases.”

Depression and heart disease have long been linked, but scientists haven’t known exactly why. It’s likely that the lifestyle factors common in people with depression, such as a lack of physical activity, smoking, alcohol abuse and a poor diet, contribute to the development of cardiovascular disease. However, the latest research suggests both diseases have a genetic link.

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