Substitutions of E104A, M292T, R118Q, M443K, E148K, and F84L in the NDUFS2 subunit in the Q module lead to Leigh syndrome [16,17], while R138Q, R333Q, and M292T mutations of NDUFS2 result in a Leigh-like syndrome [17]. The gene discussed is NDUFS2; the disease is Leigh syndrome.