Autosomal recessive disorders are monogenic genetic disorders, meaning that a gene requires two genes to be diseased at the same time in order to express the trait, hence the term recessive gene. Most inherited metabolic diseases are autosomal recessive, including phenylketonuria, pyruvate kinase deficiency, hepatomegaly, glycogen storage, hemoglobin deficiency, sickle cell anemia, galactosemia, and albinism, etc. They are characterized by healthy parents who are carriers of the disease-causing gene, pure congeners, 25% of siblings with the same chance of disease in both sexes, 25% normal, and 50% heterozygous. The patients are pure congeners, 25% of the siblings have the same chance of developing the disease; 25% are normal; 50% are not affected but are heterozygous and have a chance of developing the disease in their offspring. The incidence of the disease is significantly higher in consanguineous marriages. Autosomal recessive inheritance means that the causative gene is a recessive pair of genes on the autosome, and individuals with only one causative recessive gene do not show symptoms, but are carriers of the causative gene. Prenuptial screening and counseling, prenatal screening can effectively reduce the birth of affected children. Prenatal screening is mainly for diseases for which there is no good treatment, and its purpose is to prevent the birth of children with defects.