Concept explainers
C.1Identify the normal functions of the genes whose mutations are associated with development of cancer.
RBI(retinoblastoma)
c
p
APC(familial adenomatous polyposis)
Which of these genes would you classify as a protooncogene and which as a tumor suppressor gene? Explain your categorization for each gene.
To review:
To identify normal function of the given genes, as the mutation of these genes is related to cancer development.
The normal function of
The normal function of
The normal function of
The normal function of APC is to be identified.
The proto-oncogene and tumor suppressor genes is to be classified.
Introduction:
Proto oncogenes are those which perform normal function in the cell cycle. Mutation in proto oncogenes results in over expression of proto oncogenes which leads to uncontrolled cell division, now, they are termed as oncogenes. On the other hand, genes normally faction in DNA damage repair and control the normal cell cycle. If mutation occurs in this gene, they lose their function and DNA damage cannot be repaired; in such condition, the cell is termed as transformed, and it undergoes uncontrolled cell division.
These genes prevent cell transformation and maintain a normal cell cycle and are termed as tumor suppresser genes.
Explanation of Solution
RB1 normally inhibit the
APC (Adenomatous polyposis coli) functions as a tumor suppresser gene. It is involved in proteolytic cleavage and degradation of
Proto oncogenes accelerate rate of normal cell division and are responsible for the formation of tumors. Tumor suppresser genes suppress the formation of tumor.
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Chapter C Solutions
Genetic Analysis: An Integrated Approach (3rd Edition)
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