how can I interpret the fold change of Dseq2
1
0
Entering edit mode
@bioinformatics-10931
Last seen 2.9 years ago
United States

I have a question regaridng the conditon 

my condition is like below 

condition <- factor(c(rep("CondA", 5),rep("ConB", 5)))
> condition
 [1] CondA CondA CondA CondA CondA ConB  ConB  ConB  ConB  ConB 
Levels: ConB CondA​

what can I understand from log2fold change. does it mean that a gene from condA is higher when it is positive and or lower when it is negative  in regards to conB?

I did vignette("DESeq2") then I looked at More information on results columns which says 

log2 fold change (MLE): condition treated vs untreated" but it does not explian anything more . This is the explanation given here 

For a particular gene, a log2 fold change of -1 for condition treated vs untreated means that the treatment induces a multiplicative change in observed gene expression level of 2−1=0.5compared to the untreated condition. If the variable of interest is continuous-valued, then the reported log2 fold change is per unit of change of that variable.​

what if we use Count values?I know that it does  log2 scale but does it add +1 to it or just log2? do you safegaurd againts outliers ? do you get averge or do you get median ? 

How was it calculated ? Treated-Untreated? or Treated/untreated ? can you please comment on this ?

 

After reading their manuscript and manual of the package, I found that it is somehow calculated based on correlation coeficient of the GLM regression which is still a bit fuzzy to me. This is important because of the fact that I see a data where the fold change Treated/Control shows upregulation while the log2 fold change coming from Dseq2 gives down regulation and I have no idea why ? so would it be possible for someone to explian how they calculate this log2 fold change?

deseq2 • 2.8k views
ADD COMMENT
0
Entering edit mode
ta_awwad ▴ 10
@ta_awwad-11382
Last seen 5 months ago
Frankfurt am Main

browseVignettes("DESeq2")

ADD COMMENT
0
Entering edit mode

@ta_awwad please read my question carefully 

ADD REPLY

Login before adding your answer.

Traffic: 843 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