Table 1.

Respiratory chain (RC) activity

		Complex I* (NADH-CoQ1 red)	Complex II* (succ-CoQ1 red)	Complex III* (DBH2-cit C red)	Complex IV* (COX)	Complex V* (ATPase)	Citrate synthase†
Patient 1	Muscle	2.6	14.8	15	8.8	61	274
	Fibroblasts	9.7	6.9	73	58	40	321
Patient 2	Muscle	3.7	16.9	26	22	70	249
	Fibroblasts	6.7	14.4	110.2	12	60.6	136.5
Referencevalues	Muscle	15–31	20–40	80–160	80–180	100–220	90–200
	Fibroblasts	13–34	10–20	95–155	70–170	60–110	100–250

*Values refer to citrate synthase activity; †nmol/min/mg protein.