DNA microarrays allow researchers to analyze gene expression across an entire genome. Microarrays contain many copies of single genes arranged on a small chip. By detecting differences in gene expression levels between cell populations, microarrays can identify genes involved in processes like development, cancer, and cellular responses. Microarrays have been used to identify two subtypes of diffuse large B cell lymphoma with distinct gene expression profiles, which helps physicians predict patient outcomes and guide development of targeted cancer treatments.

1. Microarray
technology

2. Functional genomics = The
ability to perform genome-wide
patterns of gene expression and
the mechanisms by which gene
expression is coordinated.

3. Genome = The complete
complement of an organism’s
genes; an organism’s genetic
material.

4. Genome sizes and the Numbers
of Genes.

5. DNA microarrays can be used
to detect differences in the
levels gene expression in
different populations of cells on
a genome-wide level.

6. Gene expression = A gene’s ability
to make a gene product.
Most genes code for proteins
(protein encoding genes) that
when expressed, produce a gene-
specific protein.

7. DNA Microarrays
 A small 1 square centimeter chip that’s divided into thousands
of squares.
 Each square contains many copies of a single gene.
 Originally developed by Patrick Brown at the Stanford University
School of Medicine to determine which genes are involved in
yeast cell sporulation.

8. Applications of DNA microarray
analysis.
 Genes that are involved in the development of an organism.
 Genes that are activated as a family of genes (gene expression
profiling).
 Genes that are involved in human cancers.
 Earlier diagnosis of human cancers

9. Example of a cancer subtype determined via DNA
microarray analysis.
 Two subtypes of diffuse large B cell lymphoma.
 One group of tumor cells expressed a large group of genes that
are involved in early B cell development.
 Another group of tumor cells expressed a large group of genes
that are involved in late B cell development.

10. Cancer subtypes.
 Physicians can determine which cancer subtype a patient has
and can predict patient survival chances.
 Companies are trying to develop alternative drug treatments for
cancer subtypes that are not responsive to current drugs.