Question

Several members of the same family were diagnosed with he same kind of cancer when they were unusually young. Which one of the following is the most likely explanation for this phenomenon? It is possible that the individuals with the cancer have ___________.
A.

Inherited a cancer-causing gene that suffered a mutation in an ancestor's somatic cells
B.

Inherited a mutation in a gene required for DNA synthesis
C.

Inherited a mutation in a gene required for mismatch repair
D.

Inherited a mutation in a gene required for the synthesis of purine nucleotides
E.

Inherited a mutation in a gene required for the synthesis of pyrimidine nucleotides

Answer 1

Answer:

c

Explanation:(c) Inherited a mutation in a gene required for mismatch repair

Answer 2

Answer:

(c) Inherited a mutation in a gene required for mismatch repair

Explanation:

Gene mutations are occasional changes that occur in genes, that is, the procedure by which a gene undergoes a structural change. Mutations involve the addition, deletion or substitution of one or a few nucleotides of the DNA strand. Mutation provides the emergence of new forms of a gene and, consequently, is responsible for gene variability.

It is common for several members of the same family to have the same genetic mutations, as the gene affected by the mutation may condition a trait that DNA cannot repair. An example of this is the family shown in the question above, where several people were diagnosed with the same type of cancer while still young. What probably happened in this family was that people diagnosed with cancer inherited a mutation in a gene needed to repair incompatibility.