Various tests failed to establish the cause of the disease and the child’s life was at risk. Charity Fund Life Genome financed a comprehensive molecular genetic study of the child and his parents, which allowed to identify the cause of the boy's clinical condition. The specific features of the identified mutations led to severe heart damage and meager extracardiac symptoms, which prevented the timely diagnosis of the illness and prescription of adequate treatment. Genetic research helped to establish metabolic heart disease. It will allow the doctors to provide effective treatment for the child to return to a normal life.