A test that measures fragments of genetic material in saliva was nearly 90 percent accurate in identifying children and adolescents whose symptoms persisted for at least a month. In contrast, a concussion survey commonly used by doctors was right less than 70 percent of the time. Researchers did an experiment that involved 50 concussion patients between the ages of 7 and 18.
If the experimental test pans out, “a pediatrician could collect saliva with a swab, send it off to the lab and then be able to call the family the next day.” After a concussion, injured brain cells try to heal themselves. As a part of this process, brain cells release tiny fragments of genetic material called microRNAs. Some of these fragments eventually turn up in blood and even in saliva. The team measured levels of many different microRNAs in the samples, and eventually they identified a handful that let them predict how long symptoms would last. They also identified one microRNA that predicted which children would have a specific concussion symptom: difficulties with memory and problem solving.