A microarray is a tool used in genetic research to determine the mRNAs being produced in a particular tissue, and their relative level of expression. Known genes can therefore be assayed for their expression in different situations. One use of the technology is in cancer diagnosis and treatment. If a known gene functions as a tumor suppressor, predict which of the following pieces of evidence would be most useful in diagnosis of a cancer due to a mutation in this tumor-suppressor gene.
A) The tissue sample shows a high level of gene expression relative to a control (noncancerous) sample.
B) The tissue sample responds to treatment with a mitosis-promoting compound.
C) The mRNAs for the targeted tumor suppressor sequence are not being produced.
D) The mRNAs for cyclins and kinases show unusually high levels of expression.

Question

Quizplus · Accepted Answer

If the tumor suppressor gene is mutated and not producing its mRNA, this would be the most useful evidence for the diagnosis of a cancer due to a mutation in this gene. Option A is not specific to the tumor suppressor gene and could be seen in a variety of scenarios. Option B is not directly related to the function of the tumor suppressor gene. Option D is related to the function of cyclins and kinases, but does not provide evidence specific to the tumor suppressor gene being mutated.

A Microarray Is a Tool Used in Genetic Research to Determine