no population term should have a has_penetrance relation - CHECK FAILURE:  expected 0 but got 2
name	uniquename	cvterm_name	uniquename
  [null]	4bb1e87e6d6b95f9-genotype-2	variable cell size at division [has_penetrance] low	PMID:26366556
  [null]	72d1b19a5566d798-genotype-2	decreased mating efficiency [has_penetrance] high	PMID:41873186