Regarding Down syndrome,which of the following statements is TRUE?
A) Down syndrome is a sex-linked hereditary condition.
B) Down syndrome results from a lack of an important enzyme and is linked to very low levels of dopamine.
C) Down syndrome is a condition caused by an extra chromosome at pair 21.
D) Down syndrome results from an insufficient supply of thyroid hormone.

Question

Quizplus · Accepted Answer

Down syndrome is caused by the presence of an extra copy of chromosome 21, resulting in a total of 47 chromosomes instead of the typical 46. It is not a sex-linked condition, nor is it related to a lack of enzyme or low dopamine levels. While thyroid hormone imbalances can occur in individuals with Down syndrome, it is not the primary cause of the syndrome.

Regarding Down Syndrome,which of the Following Statements Is TRUE