1. You were given the following scenario in class: You are a traveling physician stationed in a small area of the Carpathian mountains. A few of your patients have urine that turns black when it is exposed to air. You suspect that your patients have a recessive disease called Alkaptonuria. The gene for Alkaptonuria (ALK) is on human chromosome 9 and is linked to the gene encoding the ABU blood group. Here are the genotypes and phenotypes for different blood types.

Blood types are normally denoted IA, IB and i (i= 0). Both A and B alleles are dominant over 0. The A and B alleles are co-dominant. Here is a pedigree with affected individuals indicated in black. The two alleles at the ALK locus are ALK- (wild type) and ALK- (mutant). The blood types for this family are also noted on this pedigree.

The daughter marked with the arrow:

A. Inherited a parental type gamete from her father B. Inherited a recombinant type gamete from her father

C. You cannot determine if she inherited a parental or a recombinant gamete from her father

Phenotype A B AB 0 Genotype IA IA or IAI IB IB or IBI IA IB ii AB O B AB, 3 B A 2 A