Closed:Limma outputs different results for same sample?
0
2
Entering edit mode
3.2 years ago
DareDevil ★ 4.3k

in the limma user manual, page 41-43 it provides two ways of calculation of DEGs

Approach1

#Differentially expressed genes can be found by
> fit <- lmFit(eset, design)
> fit <- eBayes(fit)
> topTable(fit, coef="Grp1vsGrp2", adjust="BH")

Approach 2;

#Differentially expressed genes can be found by
> fit <- lmFit(eset, design)
> cont.matrix <- makeContrasts(Grp1vsGrp2=Grp1 - Grp2, levels=design)
> fit2 <- contrasts.fit(fit, cont.matrix)
> fit2 <- eBayes(fit2)
> topTable(fit2, adjust="BH")

But I get different output for these methods:

Approcah1: output

                 ID     logFC   AveExpr         t      P.Value    adj.P.Val          B
1   GE_BrightCorner 14.034775 14.142391 48.329231 1.062840e-06 5.771813e-06  5.9423764
2        DarkCorner  3.526284  3.681083 11.510530 3.202467e-04 4.538190e-04  1.0973086
3        DarkCorner  4.438930  4.005311 24.177036 1.695687e-05 4.254662e-05  4.0948249
4      A_23_P117082 12.930345 12.460447 67.487497 2.788662e-07 4.420224e-06  6.4346613
5     A_33_P3246448  4.475369  4.365248 24.873738 1.514011e-05 3.896822e-05  4.1925378
6     A_33_P3318220  4.395836  4.075980 22.628496 2.207786e-05 5.232768e-05  3.8608390
7     A_33_P3236322  4.103927  4.176582 23.902379 1.774740e-05 4.407702e-05  4.0550613

Approach 2: output

               ID       logFC   AveExpr           t     P.Value adj.P.Val         B
1   GE_BrightCorner -0.21523164 14.142391 -0.52407752 0.627849111 0.8757925 -6.501968
2        DarkCorner -0.30959707  3.681083 -0.71459481 0.514243534 0.8245442 -6.370012
3        DarkCorner  0.86723802  4.005311  3.34001263 0.028713468 0.3393645 -3.441232
4      A_23_P117082  0.93979506 12.460447  3.46841753 0.025505731 0.3271261 -3.309127
5     A_33_P3246448  0.22024196  4.365248  0.86556019 0.435430560 0.7847096 -6.243565
6     A_33_P3318220  0.63971250  4.075980  2.32854199 0.080197184 0.4662019 -4.575855

Expect AveExpr all other parameters are different

limma ebayes topTable microarray • 436 views
ADD COMMENT
This thread is not open. No new answers may be added
Traffic: 2984 users visited in the last hour
Help About
FAQ
Access RSS
API
Stats

Use of this site constitutes acceptance of our User Agreement and Privacy Policy.

Powered by the version 2.3.6