A microarray is a tool used in genetic research to determine the relative level of expression of mRNAs in a particular tissue. One use of the technology is in cancer diagnosis and treatment. Which of the following pieces of evidence would support diagnosis of a cancer due to a mutation in a 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

Tumor suppressor genes help prevent uncontrolled cell growth. A mutation in a tumor-suppressor gene often leads to a loss of function, meaning the gene's product (in this case, mRNA and subsequently the protein it encodes) is not produced or is produced in lower quantities. This can remove the cell's ability to regulate cell division properly, leading to cancer.

A Microarray Is a Tool Used in Genetic Research to Determine