A parental mystery: Mr. and Mrs. Smith have just arrived homewith their new baby. As soon as they walk in the door, they get acall from the hospital maternity ward. The nurse who discharged theSmiths is calling to say he is now worried that she sent the wrongbaby home with them. They return to the hospital for a battery ofblood tests to clear up the confusion. The results are found in thetable below:
Individual
|
ABO Blood Type
|
MN Blood Type
| Hemoglobin Type
(H—normal; h—mutant
hemoglobin, sickle cell) |
Mr. Smith | Type A | Â Â Â Â Â Â Â Â Â Â Â MM | Â Â Â Â Â Â Â Â Â Â Â Hh |
Mrs. Smith | Type B | Â Â Â Â Â Â Â Â Â Â Â MN | Â Â Â Â Â Â Â Â Â Â Â HH |
Baby Emma | Type O | Â Â Â Â Â Â Â Â Â Â Â NN | Â Â Â Â Â Â Â Â Â Â Â Hh |
Help them interpret the results of the blood test. Could babyEmma be their daughter? Why or why not?
Both the blood-type systems are examples of codominance, andsickle-cell anemia (hemoglobin type) is an example of an autosomalrecessive trait that also exhibits codominance. Help them interpretthe results of the blood test. Could baby Emma be their daughter?Why or why not?
