Scott was curious if adults with ApoE4 and high vascular burden had a higher risk of depression.
She found this not to be the case, but found that both factors independently increased the likelihood.
That doesn't mean that people who have the gene are necessarily going to develop depression, Scott clarified to Daily Mail Online.
"There are some genes that are deterministic, but in this one, just because you have the gene doesn't mean you will develop depression. There are also a lot of other things like vascular health that play a huge role," said Scott, PhD candidate in clinical psychology.
The study was conducted on a pool of 3,203 participants, following them as they aged from 53 to 71 years old.
They did this, Scott explained, because it showed that this gene in particular makes it more likely for people to develop depression as they get considerably older. the people who had ApoE4 reported more symptoms of depression as they aged.
Prior research findings were not consistent regarding the gene and its link to depression, Scott explained.
They were usually done with small sample groups, too young a sample, or with data that wasn't collected during a long enough period of time.
"You do statistically have a higher risk of developing depression if you have ApoE4, but it's not deterministic. You can't change your genes, but you do have some control over your health," she explained.
She also emphasized the importance of finding links between genetics and depression, as well as other psychological disorders.
"The whole goal of doctors and psychologists is to identify genetic risk factors so we can make treatments as individualistic and precise as possible," Scott said. "We're always searching for a genetic link to psychopathology."
Five signs your mental health is under strain
Licy Lyus, the information manager at the mental health charity Mind set out the lesser-known symptoms:
• You become less social - this may include cancelling plans and putting off seeing friends and family, The Independent reported.
• You can't concentrate - you may also have problems thinking or speaking clearly, and notice a worse memory.
• Your sleep is impacted - this may include difficulty getting up in the morning or sleeping excessively.
• You feel numb - mental health problems can cause you to feel detached from your surroundings.
• You have physical symptoms - these could include sweating, shaking or feeling nauseous.