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Log2 fold change heatmap

Hi,

I have microarray data set where two conditions (Control versus KD) were compared. I want to have generate a heatmap which depicts the log2 fold change for subset of genes. As my result table reflects the Log2_foldchanges of KD samples,in order to find the corresponding log2_foldchanges in Control samples, I multiplied the log2_foldchanges in KD samples by -1 and generated the heatmap out of it. For an example

              Control_log2FC                       KD_log2FC
Gene_A        -2.3                                 2.3
Gene_B         1.7                                -1.7
Gene_C         4.2                                -4.2

Is my approach to generate the log2_foldchange heatmap is right?

Any help would be appreciated.

Thanks in advance.

Regards
Dino

log2foldchange heatmap microarray

2 answers

Well, the log2FC is, by definition, a fold change between groups, so KD_log2FC contains both KD and control samples. But yes, if you want control to be the numerator then you just change the sign,

Thank you Devon. I hope the heatmap I generated with between control_log2Foldchange(changing the sing) and KD_log2foldchange(without changing sign) makes sense. Thank you once again for your guidance

For me, it doesn't make sense. You will be duplicating the information in the heatmap with two columns showing the same information.

Yeah, I'm rather hoping that Dino doesn't think the fold-changes represent individual groups.

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