I have small subset of genes that have specific characteristic (e.g., TFBS in their UTRs). Checked enrichment in all set using permutation test (p value = 0). However, only small subset of genes have this TFBS and I don't know is it worth analyzing (e.g., expression, conservation) these genes as set is very small.
Total number of genes in set = 20000
Number of genes with TFBS = 8
Permutation test p value = 0 (aka, all set (20000 genes) is enriched for this TFBS compared to a genomic background)
How to determine if set size is statistically valid (8 genes out of 20000)? Any test in R?
Is it worth analyzing such a small set of genes and try to show how interesting and important is their biology?