Journal of Proteomics & Bioinformatics - Open Access
Research Article JPB/Vol. S1/Special Issue 2008
95th ISCA –Bioinformatics Section ISSN:0974-276X Volume S1: S055-S065(2008) - S055
Microarray Analysis of Differentially Expressed Genes Between Diabetes vs Healthy
Allam Appa Rao, Shyambabu M, Srinubabu Gedela
Received April 20, 2008; Accepted May 15, 2008; Published May 25, 2008
Citation: Allam AR, Shyambabu M, Srinubabu G (2008) Microarray Analysis of Differentially Expressed Genes Between
Diabetes vs Healthy. J Proteomics Bioinform S1: S055-S065. doi:10.4172/jpb.s1000010
Copyright: © 2008 Allam AR, et al. This is an open-access article distributed under the terms of the Creative Commons
Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original
author and source are credited.
Abstract
The expression profling of diabetes vs. healthy is a method of identifying genes potentially involved in the pathogenic
process. Microarray analysis enable one to determine the relative level of expression of practically all genes in a genome,
allowing the prediction of cellular plans for protein synthesis to be established. We therefore took the approach of using
microarray analysis to provide a list of genes that are differentially expressed between diabetes vs. healthy. Statistical
methodologies are employed for interpretation of microarray results. The present paper discusses the introduction to
microarray analysis and statistical methods along with the application of our present study on differentially expressed
genes of diabetes vs healthy.
Introduction
Completion of the human genome project, and the
availability of complete genomes for model organisms,
provided unprecedented prospects to the scientifc community
to carry out investigations regarding the greater mysteries
of life at the molecular level, i.e. “ from the bottom”. The
availability of several genomic blueprints has allowed new
approaches that are based on comprehensive molecular
analyses (and which enhance the understanding of biological
systems) to be devised especially for biomedical applications.
These new approaches offer the potential to describe specifc
types of genetic changes as well as patterns of altered gene
expression and functions that defne, for instance, actual
medical problems in the context of, but not entirely based
on, symptoms. It is anticipated that these new methods will
lead to identifcation of previously un- known features of
individual disease characteristics and profle progression
and response to treatment on the molecular basis. One of
the most powerful tools that has been developed as a vehicle
for carrying out such comprehensive analyses is the DNA
microarray, or the “Gene chip”, which consists of a fat
solid support with multiple probes that can be used to yield
analytical signals (Suzuki et al, 2007).
Since its inception, DNA microarray technology has
gained widespread popularity for several reasons, including
the fact that it allows a global snapshot of an organism’s
gene expression at a given point time to be obtained. This
is important because it is widely believed that thousands of
genes and their products in a given living organism function
in concert in a complicated and well-coordinated way to
sup- port its activities. Thus, a technology that allows such
a global picture to be obtained enhances the understanding
of the molecular- level biology of an organism and is highly
desirable from that perspective. Traditional molecular biology
methods of research have generally worked on a single
experiment basis, determining the functions of a specifc
gene in given physiological, chemical and/or biochemical
conditions, which means that the throughput is very limited
and a comprehensive picture is hard to obtain.
Biological Background
Perhaps one of the most fundamental biological precepts
is the crucial role played by proteins as functional molecules
of living cells. They are known to be responsible for energy
production, biosynthesis of macromolecular components,
maintenance of the structural architecture of the cell and
response to external stimuli. Specialization of cellular
functions occurs when certain specifc proteins are produced
to direct the essential activities of a given cell type. These
proteins may be synthesized when the need arises for non-
routine functions such as response to environmental results.