Question

Describe three types of genetic changes that commonly convert a proto-oncogene to an oncogene. Explain how the genetic changes are expected to alter the activity of the gene product.

Short answer

The three types of genetic changes that commonly convert a proto-oncogene to an oncogene include gene amplification that results in overproduction of the gene's protein product, point mutation that can increase the protein product’s activity level or make it active when it shouldn’t be, and chromosomal translocation that can result in a fusion gene with possible oncogenic properties or increased protein expression. All these genetic changes result in the promotion of uncontrolled cell growth.

Step-by-step solution

Identification of genetic changes

The three types of genetic changes that commonly convert a proto-oncogene to an oncogene are: 1. Gene Amplification, 2. Point mutation and 3. Chromosomal translocation.

Detailed explanation of each genetic change

1. Gene Amplification: An increase in the number of copies of the proto-oncogene can lead to overproduction of the proto-oncogene’s protein product, consequently increasing cell division and growth.\n2. Point mutation: Point mutations in the proto-oncogene or in its regulatory region can change the gene’s activity. For example, a mutation might increase the protein product’s activity level or make the protein active when it should not be.\n3. Chromosomal translocation: Translocations can result in a fusion of a proto-oncogene with another gene. The fusion protein product may have oncogenic properties. Alternatively, the translocation can result in increased expression of the proto-oncogene.

Correlation with the alteration in gene product

Each of these genetic changes leads to a shift in the functioning of the proto-oncogene product. Gene amplification results in an overproduction of the protein which in turn enhances cell growth and division. Point mutation can either increase the protein’s activity level or make the protein active when it should not be, both scenarios leading to uncontrolled cell growth. Chromosomal translocation resulting in a fusion gene leads to a new protein product with possible oncogenic properties, or it could lead to overexpression, both of which could fuel uncontrolled cell growth.