In 1990, a woman was wrongly convicted of poisoning her infant son and was sentenced to life in prison. Her conviction was based on laboratory work that wrongly identified ethylene glycol as present in her son's blood and in the formula he drank prior to his death. The actual cause of the infant's death, a metabolic disease, was eventually disclosed as a result of analytical work done by scientists who believed the mother was wrongly convicted. On the basis of the scientists' work, the conviction was overturned. This real-life case serves as the launching point for a biochemistry laboratory experiment, which uses polymerase chain reaction. Students design their own primers, amplify two biological samples, and analyze the results by gel electrophoresis to determine if their patient has a genetic mutation. This genetic mutation causes the metabolic disease, which if present can be used to "solve" the case. (Contains 1 table and 1 figure.)