Concept explainers
The accompanying pedigree shows the transmission of albinism (absence of skin pigment) in a human family.
What is the most likely mode of transmission of albinism in this family?
Using allelic symbols of your choice, identify the genotypes of the male and his two mates in generation I.
The female I-1 and her mate, male I-2, had four children, one of whom has albinism. What is the probability that they could have had a total of four children with any other outcome except one child with albinism and three with normal pigmentation?
What is the probability that female I-3 is a heterozygous carrier of the allele for albinism?
One child of female I-3 has albinism. What is the probability that any of the other four children are carriers of the allele for albinism?
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