Which disability is known as trisomy 21?

Which disability is known as trisomy 21?

• A. Cerebral palsy
• B. Attention-deficit/hyperactivity disorder
• C. Tourette syndrome
• D. Down syndrome

Answer: (D)

Having an extra copy of chromosome 21 is what defines Down syndrome, also known as trisomy 21. This chromosomal difference leads to varying degrees of intellectual disability and characteristic physical features, and it is the reason the condition is described as trisomy 21. The other conditions arise from different causes: cerebral palsy results from brain injury or development issues, ADHD is a neurodevelopmental disorder marked by inattention and hyperactivity, and Tourette syndrome involves motor and vocal tics.

Having an extra copy of chromosome 21 is what defines Down syndrome, also known as trisomy 21. This chromosomal difference leads to varying degrees of intellectual disability and characteristic physical features, and it is the reason the condition is described as trisomy 21. The other conditions arise from different causes: cerebral palsy results from brain injury or development issues, ADHD is a neurodevelopmental disorder marked by inattention and hyperactivity, and Tourette syndrome involves motor and vocal tics.