Allison was born with an extra 21st chromosome,which makes her more susceptible to heart defects and mental retardation.Allison has ____.

Question

Allison was born with an extra 21st chromosome,which makes her more susceptible to heart defects and mental retardation.Allison has ____.​

Quizplus · Accepted Answer

Down syndrome is caused by an extra copy of the 21st chromosome, which can lead to various health issues, including heart defects and cognitive disabilities. Fetal alcohol syndrome, Tay Sachs disease, and sickle cell anemia are caused by different genetic mutations and have distinct symptoms.

Allison Was Born with an Extra 21st Chromosome,which Makes Her