A spectrum of human developmental syndromes (such as Cornelia de Lange syndrome, Roberts-SC phocomelia syndrome, Warsaw breakage syndrome, chronic atrial and intestinal dysrhythmia syndrome, CHOPS syndrome, and alpha-thalassemia/impaired intellectual development syndrome), collectively termed “cohesinopathies”, refers to disorders resulting from variants in genes encoding the cohesin complex and its regulators (such as NIPBL, ESCO2, ANKRD11, HDAC8, DDX11, SGO1, AFF4, ATRX and others) (6). The gene discussed is AFF4; the disease is chronic atrial and intestinal dysrhythmia.