Table 1. Patient description and materials.

Patient	Mutation	Tissue (mtDNA)	Age	Reference
1	POLG R3P/A467T	Skeletal muscle	60	(13)
2	POLG Y955C	Skeletal muscle	48	(13)
3	POLG Y955C	Skeletal muscle	39	(24)
4a	POLG N468D/A1105T	Skeletal muscle	50	(24)
5a	POLG N468D/A1105T	Skeletal muscle	44
6a	POLG N468D/A1105T	Skeletal muscle	34
7a	352–364 AA duplication Twinkle	Extraocular eye muscle	73	(23)
8a	352–364 AA duplication Twinkle	Skeletal muscle	60
8a	352–364 AA duplication Twinkle	Frontal cortex	60
9a	352–364 AA duplication Twinkle	Skeletal muscle	33
10a	352–364 AA duplication Twinkle	Skeletal muscle	31
11a	352–364 AA duplication Twinkle	Skeletal muscle	20
1L	POLG R3P/A467T	Blood lymphocytes	60	(13)
2L	POLG Y955C	Blood lymphocytes	48	(13)
Controls
Δ1	Single mtDNA deletion	Skeletal muscle	60
Δ2	Single mtDNA deletion	Skeletal muscle	48
Δ3	Single mtDNA deletion	Skeletal muscle	35
Δ4	Single mtDNA deletion	Skeletal muscle	40
Δ5	Single mtDNA deletion	Skeletal muscle	5
1a	None	Skeletal muscle	32
2a	None	Skeletal muscle	36
3a	None	Skeletal muscle	51
4a	None	Skeletal muscle	53
5a	None	Skeletal muscle	55
6b	None	Skeletal muscle	72
7a	None	Skeletal muscle	32
8a	None	Skeletal muscle	55
9a	None	Skeletal muscle	62
10a	None	Skeletal muscle	66

Age of patients refers to the age at the time of the biopsy.

^aPatients and controls indicated in Figure 1.

^bControl 6 is a distant paternal relative of the POLG N468D/A1105T family members. Patients 1–3 and all single deletion cases are unrelated.