Maaslin2 heatmap FDR zero


I run multiple association for microbial abundance in a complex environment. I obtained a list of significant associations. I want to create a heatmap based on the associations come from the maaslin2 output. The tsv file shoring significant results comes FDR (qvalue or p value) as zero. However, heatmap results in significant association with strong color. How does zero FDR value is calculated according to -log(qval)*sign(coeff) and it shows up in the heatmap?

Hi @eo24a,

Thanks for your question. I’m not sure I completely understand what you are asking. I don’t think I’ve ever seen MaAsLin report a truly 0 q-val. Have you checked the settings on excel (or wherever you are viewing the significant results file) to make sure that row isn’t rounding the values?

I hope this helps! Let me know if I didn’t interpret your question correctly.