Obsessive-compulsive disorder, or OCD, is a mental health condition that can be mild or debilitating. The condition is characterized by having troubling obsessions or intrusive thoughts as well as compulsions that need to be carried out in order to temporarily soothe the anxiety caused by the distressing obsessions.

Over the years, there has been much discussion surrounding whether or not OCD is genetic and if there is a specific gene linked to OCD. Here's what you need to know about genetics and other risk factors for OCD.

OCD is partially genetic. "Genetics contribute to overall risk, but they do not completely determine whether or not an individual is going to develop the disorder," says Christopher Pittenger, PhD, Director of the Yale OCD Research Clinic.

We are a long way off from having a clear understanding of the genetics of OCD, Pittenger says, but there are indirect approaches that researchers have used to learn about the genetics of the disorder.

For example, a 2013 study published in Depression and Anxiety looked at 2,057 pediatric and adolescent OCD patients versus a control group of 6,055 people without OCD. The researchers found that OCD was much more likely to occur if a primary family member (parent, sibling, or offspring) had OCD. They were also more likely to have OCD if an immediate family member had a tic disorder, affective disorder, or anxiety disorder.

Another method of studying the genetics of OCD has been looking at twins with OCD. A 2014 review published in Psychiatric Clinics of North America studied 5,409 pairs of twins and found that 52% of identical twins (who share 100% of their DNA) both had OCD, whereas 21% of fraternal twins (who share 50% of DNA) both had OCD. This led researchers to infer that the more DNA is shared between family members, the higher the likelihood that there will be a co-occurrence of OCD. The study determined the heritability (genetic risk) for OCD is around 48% percent, meaning that a half of the cause for OCD is genetic.

Researchers are still working to identify the specific gene(s) associated with OCD. Pittenger says that genome-wide association studies or GWAS, that have been conducted trying to find a gene have been too small to determine whether there is a gene.

"We probably need studies 10 times larger before we can expect to start to find robust genetic 'hits'. Fortunately, there are two much larger GWAS studies underway," says Pittenger. This means that in the near future, we might have some more answers regarding an OCD-related gene.

Since OCD is only partially genetic, there are other risk factors for developing the condition, however, Pittenger says that like with the genetic aspect, other risk factors are not completely understood, either. Some of these risk factors include:

OCD may be partially caused by genetics, but there are other causes as well. More research needs to be conducted to determine exactly what the role is of genetics in OCD as well as how the other risk factors contribute to somebody developing OCD.

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Yes, OCD is genetic but having a parent or sibling with OCD doesn't guarantee you'll have it - Insider - INSIDER