Giving Birth to Someone Else’s Children? by Jessica Hutchison

Part II—Pedigree

Karen sought help from Dr. Margot Kruskall, a doctor at the Beth Israel Deaconess Medical Center in Boston, Massachusetts. Karen assured Dr. Kruskall that these were her children, conceived naturally, without the help of any reproductive technologies. Dr. Kruskall decided to rerun all of the HLA tests on Karen and her sons’ blood. The tests yielded similar results. This time Karen’s husband was also tested. The tests indicated that he had an HLA haplotype of 5 and 6. Dr. Kruskall also verified that Karen had a normal chromosome complement, 46 XX.

Questions

  1. Make a pedigree of Karen’s family, displaying their HLA haplotype combinations.
  2. Draw a Punnett square using Karen and her husband’s haplotypes showing the possible haplotype combinations of their offspring. Determine the probability of each of their sons’ haplotype combinations and record it on your pedigree.
  3. Which of your hypotheses from Part I are no longer likely, given this information, and why? Which of your hypotheses are still likely?

Go to Part III—Family Members

Originally published at http://www.sciencecases.org/chimera/chimera2.asp

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