Females found to carry a higher genetic risk of depression

An international research team, led by QIMR Berghofer, has revealed genetic differences in how females and males experience depression, in findings that could pave the way for more targeted intervention and treatments.

In a study published in the journal Nature Communications, scientists found that genetic factors contribute more to depression risk in females than in males. The team discovered about twice as many genetic ‘flags’ for depression in the DNA of females compared with males.

“We already know that females are twice as likely to suffer from depression in their lifetime than males,” said Dr Brittany Mitchell, senior researcher at QIMR Berghofer’s Genetic Epidemiology Lab.

“And we also know that depression looks very different from one person to another. Until now, there hasn’t been much consistent research to explain why depression affects females and males differently, including the possible role of genetics.”

The global study saw scientists analyse DNA from hundreds of thousands of people with and without depression, including 130,000 females (people with an XX chromosome) and 65,000 males (people with an XY chromosome) with depression. The team identified about 7000 changes in the DNA that could cause depression in both sexes, and about a further 6000 DNA changes (a total of 13,000) that could cause depression in females only.

Researcher Dr Jodi Thomas said the study also pinpointed how depression could show up differently for females and males. The team found that the genetic factors linked to depression overlap more with those associated with metabolic traits in females.

“We found some genetic differences that may help explain why females with depression more often experience metabolic symptoms, such as weight changes or altered energy levels,” Thomas said.

Traditionally, most drug trials and therapies are tested on males, but Mitchell and Thomas hope their work will also translate to a greater clinical understanding of female depression.

“Unpacking the shared and unique genetic factors in males and females gives us a clearer picture of what causes depression — and opens the door to more personalised treatments,” Thomas said.

"The findings highlight the importance of considering sex-specific genetic influences in studying depression and other health conditions.”

In the spirit of advancing scientific knowledge in this area, Thomas and Mitchell have made their results publicly available, allowing other scientists to analyse them further.

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