Skip to content
    Font Size
    A
    A
    A

    Inherited Metabolic Disorders

    Types of Inherited Metabolic Disorders

    Hundreds of inherited metabolic disorders have been identified, and new ones continue to be discovered. Some of the more common and important genetic metabolic disorders include:

    Lysosomal storage disorders : Lysosomes are spaces inside cells that break down waste products of metabolism. Various enzyme deficiencies inside lysosomes can result in buildup of toxic substances, causing metabolic disorders including:

    • Hurler syndrome (abnormal bone structure and developmental delay)
    • Niemann-Pick disease (babies develop liver enlargement, difficulty feeding, and nerve damage)
    • Tay-Sachs disease (progressive weakness in a months-old child, progressing to severe nerve damage; the child usually lives only until age 4 or 5)
    • Gaucher disease (bone pain, enlarged liver, and low platelet counts, often mild, in children or adults)
    • Fabry disease (pain in the extremities in childhood, with kidney and heart disease and strokes in adulthood; only males are affected)
    • Krabbe disease (progressive nerve damage, developmental delay in young children; occasionally adults are affected)

    Galactosemia: Impaired breakdown of the sugar galactose leads to jaundice, vomiting, and liver enlargement after breast or formula feeding by a newborn.

    Maple syrup urine disease: Deficiency of an enzyme called BCKD causes buildup of amino acids in the body. Nerve damage results, and the urine smells like syrup.

    Phenylketonuria (PKU): Deficiency of the enzyme PAH results in high levels of phenylalanine in the blood. Mental retardation results if the condition is not recognized.

    Glycogen storage diseases: Problems with sugar storage lead to low blood sugar levels, muscle pain, and weakness.

    Mitochondrial disorders: Problems inside mitochondria, the powerhouses of cells, lead to muscle damage.

    Friedreich ataxia: Problems related to a protein called frataxin cause nerve damage and often heart problems. Inability to walk usually results by young adulthood.

    Peroxisomal disorders: Similar to lysosomes, peroxisomes are tiny spaces filled with enzymes inside cells. Poor enzyme function inside peroxisomes can lead to buildup of toxic products of metabolism. Peroxisomal disorders include:

    • Zellweger syndrome (abnormal facial features, enlarged liver, and nerve damage in infants)
    • Adrenoleukodystrophy (symptoms of nerve damage can develop in childhood or early adulthood depending on the form.)

    Metal metabolism disorders: Levels of trace metals in the blood are controlled by special proteins. Inherited metabolic disorders can result in protein malfunction and toxic accumulation of metal in the body:

    • Wilson disease (toxic copper levels accumulate in the liver, brain, and other organs)
    • Hemochromatosis (the intestines absorb excessive iron, which builds up in the liver, pancreas, joints, and heart, causing damage)

    Organic acidemias: methylmalonic acidemia and propionic acidemia.

    Urea cycle disorders: ornithine transcarbamylase deficiency and citrullinemia

    Hot Topics

    WebMD Video: Now Playing

    Click here to wach video: Dirty Truth About Hand Washing

    Which sex is the worst about washing up? Why is it so important? We’ve got the dirty truth on how and when to wash your hands.

    Click here to watch video: Dirty Truth About Hand Washing

    Popular Slideshows & Tools on WebMD

    disciplining a boy
    Types, symptoms, causes.
    fruit drinks
    Eat these to think better.
    embarrassed woman
    Do you feel guilty after eating?
    diabetes supply kit
    Pack and prepare.
    handful of vegetables and vitamins
    Diet tips and mistakes.
    birth control pills
    Which kind is right for you?
    Remember your finger
    Are you getting more forgetful?
    sticky notes on face
    10 tips to clear your brain fog.
    Close up of eye
    12 reasons you're distracted.
    Trainer demonstrating exercise for RA
    Exercises for your joints.
    apple slices with peanut butter
    What goes best with workouts?
    woman having a good day
    Revitalize your life.

    Pollen counts, treatment tips, and more.

    It's nothing to sneeze at.

    Loading ...

    Sending your email...

    This feature is temporarily unavailable. Please try again later.

    Thanks!

    Now check your email account on your mobile phone to download your new app.

    Women's Health Newsletter

    Find out what women really need.