www.gusucode.com > bioinfo 案例源码程序 matlab代码 > bioinfo/NormalizeMicroarrayDataExample.m

    %% Normalize Microarray Data
% This example illustrates how to correct for dye bias or scanning
% differences between two channels of data from a two-color microarray
% experiment.
%%
% Read microarray data from a sample GPR file.

% Copyright 2015 The MathWorks, Inc.

maStruct = gprread('mouse_a1wt.gpr');

%%
% Extract gene expression values from two different experimental
% conditions.
cy5data = magetfield(maStruct, 'F635 Median');
cy3data = magetfield(maStruct, 'F532 Median');

%%
% Normalize |cy3data| using |cy5data| as reference and plot the results.
Normcy3data = mainvarsetnorm(cy5data, cy3data, 'showplot', true);

%% 
% Under perfect experimental conditions, data points with equal
% expression values would fall along the M = 0 line, which represents a
% gene expression ratio of 1. However, dye bias caused the measured values
% in one channel to be higher than the other channel, as seen in the Before
% normalization plot. Normalization corrected the variance, as seen in the
% After normalization plot.