How can a mutation in a tumor suppressor behave as a recessive allele at the cellular level but appear as a dominant allele in pedigree analysis?

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At the cellular level, both alleles of a tumor suppressor gene typically need to be mutated for cancer to develop, making it recessive. However, in a pedigree, the predisposition to cancer can appear dominant because inheriting one mutated allele increases the risk of cancer, and the second mutation can occur somatically.

How Can a Mutation in a Tumor Suppressor Behave as a Recessive