Don has been diagnosed with adenomatous polyposis - a type of colon cancer. Investigation of Don's family history yields the following pedigree for colon cancer. In order to isolate the disease gene responsible for this type of colon cancer you look for SNPs linked to the disease phenotype. You score each family member for the presence of a specific SNP with 4 alleles: 1, 2, 3, and 4. The results are listed on the pedigree. Based on the pedigree, which of the following is likely true? A. It is likely Don has a hereditary form of colon cancer B. All members of Don's family carry a germ-line mutation in a tumor suppressor gene C. Don inherited one hit' in a tumor suppressor gene and acquired a second spontaneous mutation in the remaining functional allele C. a and C D. All of the above apply Based on the pedigree which allele is likely associated with an inherited predisposition to colon cancer? A. Allele 1 B. Allele 2 C. Allele 3 D. Allele 4 E. An association cannot be established One year later you identify the disease gene, 'adenomatous polyposis coli' or APC, and perform an analysis to find the mutations causing cancer in this affected family. Using PCR followed by sequencing techniques, a nonsense mutation in the APC gene of Don is found. How does this mutation affect the protein produced? A. A different amino acid is specified resulting in a loss of function B. A different amino acid is specified resulting in a gain of function C. A primary mRNA transcript is not generated and synthesis of this protein is lost D. A codon specifying an amino acid is changed to a stop codon resulting in a loss of function E. Non of the above