We next examined whether AA impaired DNA repair by evaluating the levels of predominant DNA repair proteins, including excision repair cross-complement rodent repair deficiency, complementation group 1 and 2 (ERCC1 and ERCC2), methylguanine methyl transferase (Mgmt) and Poly [ADP-ribose] polymerase 1 (PARP1). Here, ERCC1 is linked to hyperinsulinemic hypoglycemia, familial, 4.