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.