Model matrix not full rank
1
0
Entering edit mode
@sallybadawi-16174
Last seen 5.2 years ago

Hi all, 

I would like to use DESeq2 to analyze a time series experiment of 6 time points each time point with 8 replicates. 3 time points are made in different time than the others, therefore they have a different batch.

My aim is to detect the genes varying over time in response to the treatment I'm doing.

While trying to include batch in the design its giving the error model matrix not full rank. When analyzing without including batch effect, I get a high number of significant genes and PCA plot is clustering samples based on batch not on time. Any help with this? 

Sample ID  time  batch 
Sham0.1 t0 b1
Sham0.2 t0 b1
Sham0.3 t0 b1
Sham0.4 t0 b1
Sham0.5 t0 b1
Sham0.6 t0 b1
Sham0.7 t0 b1
Sham0.8 t0 b1
Sham15I.1 t1 b2
Sham15I.2 t1 b2
Sham15I.3 t1 b2
Sham15I.4 t1 b2
Sham15I.5 t1 b2
Sham15I.6 t1 b2
Sham15I.7 t1 b2
Sham15I.8 t1 b2
Sham45.1 t2  b1
Sham45.2 t2  b1
Sham45.3 t2 b1
Sham45.4 t2 b1
Sham45.5 t2 b1
Sham45.6 t2 b1
Sham45.7 t2 b1
Sham45.8 t2 b1
Sham15IR.1 t3 b2
Sham15IR.2 t3 b2
Sham15IR.3 t3 b2
Sham15IR.4 t3 b2
Sham15IR.5 t3 b2
Sham15IR.6 t3 b2
Sham15IR.7 t3 b2
Sham15IR.8 t3 b2
Sham1hrIR.1 t4 b2
Sham1hrIR.2 t4 b2
Sham1hrIR.3 t4 b2
Sham1hrIR.4 t4 b2
Sham1hrIR.5 t4 b2
Sham1hrIR.6 t4 b2
Sham1hrIR.7 t4 b2
Sham1hrIR.8 t5 b2
Sham24.1 t5 b1
Sham24.2 t5 b1
Sham24.3 t5 b1
Sham24.4 t5 b1
Sham24.5 t5 b1
Sham24.6 t5 b1
Sham24.7 t5 b1
Sham24.8 t5 b1

 

design~ batch + time and for deseq function LRT test with reduced~batch

 

Thank you in advance for the help 

DESeq2 model matrix not full rank batch effect • 957 views
ADD COMMENT
0
Entering edit mode
@mikelove
Last seen 3 hours ago
United States

It looks like batch and time are confounded. This is unfortunate, and not much can be done to remove batch, as it is mixed up with biological changes over time. Next time you should prepare the libraries using a block or randomized design.

ADD COMMENT

Login before adding your answer.

Traffic: 755 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