Martha married Brian 20 years ago. They have a 22 year old son, Justin. Before they were married, Martha was dating both Brian and another man. Martha was upfront about the fact that the other man, Mike, may possibly be Justin's biological father. None of this mattered to any of them until Justin started experiencing some health problems. Justin has recently been diagnosed with kidney failure and is currently waiting for a kidney transplant. His family members have been asked to get blood tested to see if anyone is a potential donor match. To try to help her son, Martha also approached Mike to see if he would get the blood test done to see if there was a match. Mike agrees to get tested. Each of the family members has a blood type test done. The results are as follows: Justin - phenotype A/genotype AO Martha - phenotype and genotype AB Brian - phenotype B/genotype BO Mike - phenotype and genotype AB Knowing what you know about Punnett squares and the codominant inheritance of blood types, answer the following questions for extra credit. 1. If Martha and Mike were to have another child, what are the possible genotypes of their children? 2. If Martha and Brian were to have another child, what are the possible genotypes of their children? 3. Looking at Justin's genotype, which parent gave him the "A" in his blood type? 4. Finally, from the blood typing information who is Justin's daddy? 5. What is the reasoning behind your choice for number 4?
