Hello Mr. Bennardo, I think the two most common ways of adressing multiple testing in GWAS-like data is either using a Bonferroni corrected p-value threshold or by using a False Discovery Rate (FDR) approach. The documentation for the R package "qvalue" is very well written: https://www.bioconductor.org/packages/release/bioc/manuals/qvalue/man/qvalue.pdf
Hello Mr. Kengne, I had the same problem and I managed to get the perl script running by following this solution in the comments here: https://code.google.com/archive/p/popoolation2/issues/19 I hope this helps!