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a 4yr boy is brought to the pysician because developmental delays and hand flapping.his mother had learning disability and his maternal uncle had mental retardation.physical exam is consistent with fragile x.After the parents are informed of the diagnosis ,they ask if their 12yr old daughter, who has met all developmental mile stones,should be tested to determine her carrier status.which of the following is the most appropriate response by the physician?

a.I recommend testing now so that she can b prepared for what may lie ahead if she has children

b.i recommend waiting until she is older and mature enough to decide for herself if she would like to be tested.

c.lets discuss the situation with her and ask her if she would like to be tested

d.lets hold off on and discuss the options when she is ready to marry and have children

??????????????????????

a i think so

I think it might be (BBB)

A

b. FXS is x-linked dominant. so she has a 50% chance of having FXS. but she needs to make the decision herself on getting tested.

Fragile X is X-linked recessive. I think the answer is B.

bbbb

C is more logic and reseanable

A, it is x-dominant and women can be phenotypically normal even if they carrying mutation of FMR1 gen (X-inactivation), i think it is better to know about it before hands, because she can transmit the mutation to 50% of her sons and daughters.