The way that a person is affected by sleep loss is based on genetics, according to a new study, reports UPI.

Researchers at the Perelman School of Medicine at the University of Pennsylvania studied the cognitive effects of sleep-deprived people and found differences were reflected in microRNAs. Their findings were presented at the 32nd Annual Meeting of the Associated Professional Sleep Societies LLC in Baltimore.

“These findings show for the first time that miRNAs can track responses to total sleep deprivation and its detrimental combination with psychological stress and predict robust individual differences in various types of cognitive performance,” senior author Dr. Namni Goel, an associate professor of psychiatry at Penn, said in a press release.