Question

A couple (both of which are normal) has a son that has Duchenne muscular dystrophy. This is a rare sex-linked recessive disorder which causes muscle deterioration that almost always affects boys. The parents believe that the hospital mixed their child up with a normal child and sue the hospital. You have once again been called as an expert in genetics to testify. What do you tell the jury? Is it possible that these are the biological parents or did the hospital make a mistake? Fully explain your answer.

Answer 1

The muscular dystrophy is a rare X-linked recessive disorder. It generally afects boys, because they only have one copy of "X"chromosome, inherited from their mothers. So, in this case both the parents are normal. It may happen that the mother might be the carrier of the mutation, on one of the chromosome, while the other copy of the gene on other chromosome is normal.

Hence, there is a chance, that the boy child getting infected because the mother is the carrier. So, there is less likely that the hospital mixed child up.

So, there is unlikely that hospital made the mistake.