Discrepancy between signal p-value and fold change bigwig tracks around the open regions

[AayushGrover]

Hello,

I tried correlating two bigwig tracks (fold change over control and signal p-value) around the ATAC-seq peaks from the GM12878 ATAC-seq ENCODE experiment and similarly for K562 ATAC-seq ENCODE experiment. To be precise, the following are the accession codes of the files:

• GM12878 (FC): ENCFF603BJO
• GM12878 (signal p-value): ENCFF667MDI
• GM12878 (bed narrowpeak): ENCFF748UZH
• K562 (FC): ENCFF102ARJ
• K562 (signal p-value): ENCFF357GNC
• K562(bed narrowpeak): ENCFF333TAT

However, the rank correlation is only around 0.8. I would expect this to be 0.95 and above. Could you help me understand why this might be the case, especially since both tracks are created from the same bam files and hence, the same control?