Sickle cell disease is inherited. If a person is homozygous for sickle cell, they have the disease. If they are heterozygous for sickle cell, they have sickle cell trait. These people carriers but...

Sickle cell disease is inherited. If a person is homozygous for sickle cell, they have the disease. If they are heterozygous for sickle cell, they have sickle cell trait. These people carriers but normally healthy.

Use a Punnett square to calculate the possible phenotypes and genotypes for the child of a normal homozygous mother and a father with sickle cell trait.

Asked on by zysh0

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megamind-616 | Middle School Teacher | (Level 1) Associate Educator

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Using the information that was given in within the question, we are going to use the following allele representations: 

S= sickle cell trait

s = normal

We are told that the father has the sickle cell trait. We will assume that the father is homozygous for sickle cell. Therefore, 

Normal homozygous mom = ss

Homozygous sickle celled dad = SS

          s                     s

S     Ss                    Ss

S      Ss                  Ss

Thus, the probabilities of the genotype (allele combinations) and phenotype (physical appearance) frequencies of the F1 (offspring) generation would be:

Genotype Frequencies:

Ss = 100%

Phenotype Frequencies: 

100% Heterozygous carriers of sickle cell anemia.

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