Which of the following statements is true regarding PKU?

Phenylketonuria (PKU) is a genetic disorder that results from the deficiency of the enzyme phenylalanine hydroxylase, which is necessary to metabolize the amino acid phenylalanine. When untreated, the accumulation of phenylalanine can lead to severe intellectual disabilities and developmental delays, among other neurological impairments. This highlights the importance of early detection and treatment through dietary management, which can effectively prevent the detrimental effects associated with the disorder.

The other statements do not accurately describe PKU. It is not an X-linked disorder; rather, it is autosomal recessive, meaning it requires two copies of the mutated gene for the condition to manifest. PKU affects both males and females equally, so it does not primarily affect males. Additionally, PKU is not caused by an excess of collagen; it is related to the metabolism of phenylalanine and does not involve collagen. Therefore, understanding PKU's impact on mental health and function is crucial for recognizing the importance of early intervention.