Question

Iris decides that she would like to have another child, but she wants to make sure that this child does not inherit the mutated atp7b allele which causes Wilson’s disease. Iris and her partner do a genetic test and find out that they each have one atp7b allele and one ATP7B allele. In addition, one of Iris’ X chromosomes contains the recessive genetic mutation which causes red green colorblindness (X^AX^a) and Iris is heterozygote for being flatfooted (F/f), the gene for which is located right next to the ATP7B/atp7b gene on chromosome 13. Iris’ partner does not have these other two mutations.

ATP7B/atp7b will most often experience crossover with which gene?

		F/f
		XAXa
		ATP7B/atp7b

Based on the genotypes described above, if they proceed to conceive without medical intervention, what are the chances that their next child will have Wilson’s disease?

		1/4
		1/2
		3/16
		9/16
		1/16

Based on the genotypes described in the previous questions, if they proceed to conceive without medical intervention, what are the chances that their next child will have Wilson’s disease and will be red green color blind?

		1/4
		1/2
		3/16
		9/16
		1/16

Answer 1

ATP7B/atp7b gene will most often crossover with F/f gene of another chromosome.. F/f gene located in same chromosome with ATP7B/atp7b gene. Crossing over occur between nonsister chromatid of two nonhomologus chromosome.