genetics Q1 - waliid

[ArchivalUser]

Neurofibromatosis type 1 is one of the most common autosomal dominant disorders. A woman with neurofibromatosis type 1 has an unaffected partner. Which of the following is correct regarding their children?


a) The probability that each of their children will be affected is 1 in 4.

b) The probability that their second child will be affected if their first child is affected is 1 in 4.

c) The probability that their third child will be affected if their first two children are affected is 1 in 2.

d) If their first child is affected then their second child will not be affected.

[ArchivalUser]

c.

[ArchivalUser]

c.

[ArchivalUser]

not sure....
a)1/2
b)1/3
c)?1/3
d)no

[ArchivalUser]

could someone please explain this answer

[ArchivalUser]

cccccccccc

[ArchivalUser]

hey kashmala why did u opt for C. can someone explain this. it is confusing. IN AD THERE IS 50:50 CHANCE. SO IF 2 CHILDREN R AFFECTED WHERE IS THE CHANCE THAT THE 3RD CHILD WILL BE AFFECTED NO DOUBT EVERY BIRTH IS INDEPENDENT AND HAS SAME RECRRENCE RISK.

CAN U EXPLAIN PLZ.

BYE

[ArchivalUser]

When an affected individual has children, and the other partner is not affected, the probability that each child will be affected is 1 in 2

[ArchivalUser]

----------A--------A
-----A--AA-------AA
-----a--Aa-------Aa
whwere A is normal allele in both sexes n a is used for autosomal dominant allele in woman.
2/4 or 1/2 r affected