There is overlap between experimentally determined Z-flipons and Mendelian variants in a number of genes including HBA1 (hemoglobinopathies), CDKN2A (melanoma susceptibility), MC1R (red hair color, melanoma), WNT1 (osteogenesis imperfecta, type xv), NPHS1 (nephrotic syndrome, Type 1), SOX10 (Waardenburg syndrome, Type 2e), IDUA (Hurler–Scheie syndrome), LAMB3 (heterotaxy), IL17RC (familial candidiasis), and FOXL2 (blepharophimosis, ptosis, and epicanthus inversus, type I), providing direct evidence that Z-flipons do influence trait variation. This evidence concerns the gene NPHS1 and ptosis.