Several studies have observed that drug abuse leads to mental health problems. However, new research found that a person’s genetic risk for mental illness, including depression, can also make them prone to drug use.

“Our research shows that if someone is genetically predisposed towards having mental illness, they are also prone to use licit and illicit substances and develop problematic usage patterns,” Caitlin E. Carey, a PhD student in the BRAINLab at Washington University in St. Louis and lead author of the study, said in a statement Thursday. “[We] were able to compare people with various levels of substance involvement to determine whether they were also at relatively higher genetic risk for psychiatric disorders.”

Researchers looked into the data of 2,573 people who were participants of the Study of Addiction: Genetics and Environment. The team of the latest study examined the participants’ substance use and misuse and their dependency on drugs.

“[This] also allowed us to evaluate specific psychiatric disorder-substance relationships,” Ryan Bogdan, senior author of the study and director of the BRAINLab, said in the statement. “For example, we found that genetic risk for both schizophrenia and depression are associated with cannabis and cocaine involvement.”

Researchers said that the findings of the study have paved way for further studies examining the predictive power of genetic risk.

“It will now be important to incorporate the influence of environmental factors, such as peer groups, neighborhood, and stress, into this research. This will help us better understand how interplay between the environment and genetic risk may increase or reduce the risk of co-occurring psychiatric disorders and substance involvement. Further, it will be important to isolate specific genetic pathways shared with both substance involvement and psychiatric illness. Ultimately, such knowledge may help guide the development of more effective prevention and treatment efforts decades in the future,” Bogdan said.

According to National Institute on Drug Abuse, the total cost related to drug abuse is estimated at $700 billion a year. Use of illegal drugs accounts for $193 billion of total cost in healthcare, productivity loss, crime, incarceration and drug enforcement.

The study was published in the peer-reviewed Frontiers journal.