An international team of researchers have found hundreds of new genetic variants linked to depression. The study highlights unknown biological factors that underpin the illness.
Category
📺
TVTranscript
00:00Hi Lono, thank you for having me.
00:04This was a really big international effort in trying to understand the causes of depression.
00:10And so it pulled data from researchers from 29 countries around the world, where we ended
00:15up with a really large sample size, looking at about 680,000 people that had suffered
00:20from depression, and then comparing their DNA to over 4 million people that hadn't had
00:24depression before.
00:25So it's really the world's largest study into the genetics of depression.
00:28Gosh, it is big, and compiling all that data must have caused quite a headache.
00:32What did you find?
00:37We uncovered about 697 small genetic variants, so these are variations in genes that seem
00:44to be associated with risk of depression, and we're really excited about this because
00:47of 300 of these were previously unknown, so it's really increased our understanding of
00:52how biology plays a role in depression risk.
00:55So each thing that you found, on its own, can be a cause of depression, or is it a combination?
01:06It's a combination.
01:07So each of these genetic risk variants have a very small effect on their own, so no one
01:12of them is going to cause depression, but cumulatively they can increase your risk.
01:17But I think it's also important to bear in mind that even if you have a lot of these
01:22genetic variants, that that's not deterministic.
01:24That doesn't mean you will definitely get depression, it just means that you might have
01:28an elevated risk, but obviously things like environment, lifestyle, traumatic experiences,
01:34we know that those also play a really big role in the causes of depression.
01:38So Brittany, what does having this information give us?
01:44How will it benefit how we go from here?
01:50We're really excited about understanding the biology more, because this is really one of
01:55the first steps in providing better treatment.
01:57So if we know what's happening in the brain, and we know what pathways are being enriched
02:01or being activated when people suffer from depression, we can develop drugs that target
02:06these pathways and provide more tailored treatments, or potentially reuse drugs that are already
02:11on the market that are maybe used to treat other disorders, but work on those same pathways
02:17that we now know play a role in depression, and these drugs might then also provide new
02:21treatment avenues for people.
02:22Oh, that's interesting.
02:24So some of the genetic mutations or the genetics that are there can be treated with drugs that
02:30are currently on the market, but just not for depression?
02:33Yes, so that's a really kind of novel and exciting aspect of the study is what we did
02:40was by understanding the genetic variants that are linked to depression and kind of
02:45what biological processes they're involved in in the body, we've been able to map back
02:49to medications that are currently on the market.
02:53So one of the common ones that we highlight in the paper is a medication called modafinil.
02:59It's prescribed to treat narcolepsy and is often prescribed to shift workers that need
03:03to stay up through the night, and we know that that drug targets a lot of the similar
03:09pathways that occur in depression.
03:11So there's potential that this may end up being able to be used for depression.
03:16We're obviously a little way off and we don't want everyone to rush out and buy modafinil
03:22to treat their depression now, but we're very excited by that because it obviously cuts
03:26down the time significantly in getting a new treatment to patients rather than developing
03:33drugs from scratch and having to go through all the clinical trial basis.
03:37We know that it's safe, it's available, it's on the market.
03:40We just don't know if it's going to help with depression, but that's the next step
03:43in the research.
03:44Okay.
03:45We know that with depression, prevention is key.
03:48How does the research that you've been part of, how does it play into that, the prevention
03:54aspect?
03:58I think showing that the biology does play a significant role in depression risk for
04:02some people is really promising, and we've shown that if we create a genetic risk score
04:08from these identified genes that we've found, that this risk score is predictive of depression
04:14and it is able to significantly associate with people that have depression.
04:19And so the ultimate goal would be that this ends up in the healthcare system down the
04:24line and that can then be used with healthcare professionals to match if you know you're
04:30at high risk to help interventions or prevention strategies early on so we can start talking
04:36about preventing depression rather than just treating it once it's occurred.