ZNF609 and Hirschsprung disease: Recently, it has been reported that abnormal expression of circ‐ZNF609 is associated with tumours and other diseases, including renal cell carcinoma (RCC), colorectal cancer (CRC), rhabdomyosarcoma (RMS), nasopharyngeal carcinoma (NPC), gastric cancer (GC), lung cancer (LC), hepatocellular carcinoma (HCC), prostate cancer, cervical cancer (CC), glioma, Hirschsprung's disease (HSCR), vascular thyroid dysfunction, corneal neovascularization (CNV), glaucoma, neuropathic pain, myotonic dystrophy type 1 (DM1), diabetic retinopathy (DR) and lupus nephritis (LN).