Reagan is a young girl with a genetic developmental disorder. Her language development has been severely affected by this condition, and as such she has been diagnosed with a specific language impairment. Which condition is NOT likely to have contributed to this delay?

Option D

Explanation:

Complete question

Reagan is a young girl with a genetic developmental disorder. Her language development has been severely affected by this condition, and as such she has been diagnosed with a specific language impairment. Which condition is NOT likely to have contributed to this delay?

A) autism spectrum disorder

B) Down syndrome

C) fragile-X syndrome

D) PKU

Solution

Phenylketonuria (PKU) is a kind of genetic disorder in which body starts producing and building up phenylalanine amino acid. PKU arises when the Phenylalanine hydroxylase enzyme is not synthesized due to a genetic defect thereby affecting creation of neurotransmitters such as epinephrine, norepinephrine, and dopamine. Some of the symptoms of this disorder are hyperactivity, seizures, eczema, tremors etc. PKU is not connected with language development issues and hence correct option is D

"do a testcross with a homozygous recessive plant."