A geneticist was asked to investigate the inheritance of acatalasia in dogs. The nomal allele is represented by B and the mutant allele is represented by b.
The geneticist made the diagram in Fig 3.1 to show the inheritance of acatalasia in a family
of dogs. The shaded symbols indicate the dogs with acatalasia.

State the genotypes of the dogs identified as 1,2 and 3 in Fig. 3.1.
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