TLS Online TPP Program

#Question id: 12489


Achondroplasia shows autosomal dominant inheritance with complete penetrance. A man with achondroplasia has an unaffected partner of normal height. Their first two children are not affected. Which of the following is correct?

#Part-A Aptitude & General Biotechnology
  1. The probability that their next child will be affected is 1 in 2.
  2. The probability that each of their children will be affected is less than 1 in 2 because the parents of the man with achondroplasia are not affected.
  3. The mother of these children has a sister with achondroplasia. This increases the risk that the children could be carriers.
  4. If their third child is unaffected, then the probability that their fourth child will be affected is 1 in 8.