This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Genetics, Subject name: Medicine
Incidence of Down's syndrome is directly proportional to 
Select and explain. 
A. Parity, B. Consanguinity, C. Maternal age, D. Mutations
C: Maternal age
Answer: C: Maternal age 
Explanation: Ans. c (Maternal age). (Ref. Harrison, Internal Medicine, 16th ed., 383)The incidence of Down ys syndrome is highly correlated to maternal age.QUADRUPLE TEST FOR DOWN'S SYNDROME# AFP |# beta-HCG |# Unconjugated estriol |# Human placental lactogen/placental protein A |