Which autosomal recessive disorder is characterized by a deficiency in phenylalanine metabolism and can cause intellectual disability and seizures if untreated?

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Multiple Choice

Which autosomal recessive disorder is characterized by a deficiency in phenylalanine metabolism and can cause intellectual disability and seizures if untreated?

Phenylketonuria is a metabolic condition caused by a deficiency of phenylalanine hydroxylase, the enzyme that converts phenylalanine into tyrosine. When this step is impaired, phenylalanine and its metabolites build up in the blood and brain, and these substances are toxic to brain development. If this buildup isn’t addressed from birth, it can lead to intellectual disability and seizures, among other neurodevelopmental problems. The condition is inherited in an autosomal recessive pattern, which means a child must inherit two defective copies of the gene to be affected. Treatment centers on restricting phenylalanine intake through a special diet and providing tyrosine, which becomes essential because it can no longer be made from phenylalanine. Early detection via newborn screening allows dietary management that prevents cognitive impairment. The other options listed are neurotransmitters and not related to a metabolic disorder of phenylalanine processing.

Phenylketonuria is a metabolic condition caused by a deficiency of phenylalanine hydroxylase, the enzyme that converts phenylalanine into tyrosine. When this step is impaired, phenylalanine and its metabolites build up in the blood and brain, and these substances are toxic to brain development. If this buildup isn’t addressed from birth, it can lead to intellectual disability and seizures, among other neurodevelopmental problems. The condition is inherited in an autosomal recessive pattern, which means a child must inherit two defective copies of the gene to be affected.

Treatment centers on restricting phenylalanine intake through a special diet and providing tyrosine, which becomes essential because it can no longer be made from phenylalanine. Early detection via newborn screening allows dietary management that prevents cognitive impairment. The other options listed are neurotransmitters and not related to a metabolic disorder of phenylalanine processing.

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