A polymerase chain reaction (PCR) test detects genetic material from a pathogen or abnormal cell sample. Ways of collecting samples include a nasal swab, a saliva swab, or taking a sample of blood.

Even when doubt does arise in today’s digital age, it’s hard to question hard forensic evidence like DNA. The fashion industry has caught on, gaining assurance how applying physical DNA markers on ...

Ducharme is a contributor to TIME. A medical worker performs a COVID-19 test at a screening center in Saint-Denis, France, on Nov. 4, 2020. Ducharme is a contributor to TIME. If you had COVID-19 ...