Metabolic disorders are a group of genetic disorders that affect the body’s metabolism. The body needs an active metabolism to grow and function. Metabolism is your body’s ability to convert what you eat and drink into energy. This is achieved through a chain of many different chemical reactions. Metabolic disorders alter these normal chemical reactions in the body. Thus, the breakdown of proteins, carbohydrates or fats in food and drink is affected. This can cause either a buildup of toxins in the body or a decrease in the nutrients available for normal body functions. Metabolic disorders are often multisystemic disorders. This means they affect many different organs in the body. People from birth through adulthood may show signs and symptoms that reflect an underlying metabolic disorder.
A few examples of metabolic disorders include galactosemia, glycogen storage diseases, fatty acid oxidation disorders (e.g., Medium-chain acyl-CoA dehydrogenase (MCAD) deficiency, Very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency), amino acid disorders (e.g., Phenylketonuria (PKU), Maple syrup urine disease) and urea cycle disorders.
Each chemical reaction of metabolism is like a component on a circuit board. The reactions are driven by many different enzymes.
Enzymes are one of many products made by our cells. Our genes contain sets of DNA instructions for making these products. An error in any of the genetic instructions can lead to an enzyme that does not work, or to no enzyme being made at all. This can lead to a buildup of toxins or lack of nutrients. Problems with just one enzyme in a pathway can lead to a metabolic disorder.