Question

A classic experiment to identify cellular oncogenes went as follows: DNA was purified, crystallized, and put into a culture of non-cancerous cells.

If this protocol were used with a piece of human DNA containing the TP53 gene with a loss-of-function deletion mutation, then this would:

a) Promote the transformation of the transfected cells

b) Have no effect on the transformation of the transfected cells

c) Result in viral infection and replication in transfected cells

d) It is not possible to transfect non-cancerous cells

Answer 1

a) Promote the transformation of the transfected cells.

Cellular transformation is the process by which a normal cell acquires the features of cancer. Transfection is the deliberate introduction of naked DNA into a eukaryotic cell.

DNA transfections can be used to identify cellular oncogenes. When DNA containing suspected oncogene are introduced to a culture of non-cancerous cell, a few cells will take up and express them. These transfected cells will express the features of cancer cells, which confirms the oncogenes in the piece of DNA added.  

So, if this protocol were used with a piece of human DNA containing the TP53 gene with a loss-of-function deletion mutation, then this would promote the transformation of the transfected cells in the culture.