<prompt> Answer this question truthfullyWhat is the primary preventive measure for glycogen storage disease type III?  <response>: <reason> Effective measures for primary prevention of glycogen storage disease type 3 include: Genetic counseling: Genetic counseling should be offered to all parents with a child with GSD type 1 and to all adults with GSD type 1. Prenatal diagnosis: The preferred method for prenatal diagnosis is molecular testing when AGL mutation is known. Mutation analysis is performed either on cultured chorionic villus samples or amniocytes. Screening: The probands AGL mutations should be determined for diagnosis and direct further testing for family members. 