Regarding Down syndrome,which of the following statements is FALSE?
A) The age of the parents is a major factor in Down syndrome.
B) Down syndrome is caused by an extremely thin area occurring on the X chromosome.
C) While Down syndrome is genetic, it is not usually hereditary (it doesn't "run in the family").
D) Down syndrome causes moderate to severe intellectual disability and a shortened life expectancy of around 49 years.

Question

Quizplus · Accepted Answer

Down syndrome is not caused by an extremely thin area occurring on the X chromosome. It is caused by a full or partial extra copy of chromosome 21. The age of the mother is the major factor in Down syndrome, not the age of the parents. Down syndrome is genetic, but it is not usually hereditary as it typically occurs by chance. Down syndrome can cause mild to moderate intellectual disability and a shortened life expectancy, but it can vary greatly depending on the individual.

Regarding Down Syndrome,which of the Following Statements Is FALSE