Closed:high read depth and threshold for filtering

Question

[noeD]

Hello!

I am working with dna-seq data from tumor samples and I have tried to plot the frequency of my read depth. I am wondering how to choose a good threshold for the read depth in order to remove variant with low depth. Furthermore I have seen that there a some variants with a very high read depth (over 600) how is it possible? what does it mean?

Thank you in advance,

Best regards