Inherited disorders or inborn errors of metabolism are diseases which enzyme deficiency or inactivity caused by mutations in genes that code for enzymes leads to accumulation of substrate precursors or metabolites or to deficiencies of the enzyme’s products. Hundreds of disorders exist, and most are extremely rare; they are typically grouped by the affected substrate (eg, carbohydrates, amino acids, fatty acids).
Types of inherited metabolic diseases
The inherited metabolic diseases were categorized depended on metabolism pathways in the body are
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Inherited disorders of metabolism 
