Table 1.

Frequency of the pathogenic GGGGCC hexanucleotide repeat expansion of C9orf72 in patients diagnosed with sporadic ALS or sporadic FTD classified by region

		Sporadic ALS			Sporadic FTD
		n	Carriers	% (95% CI)	n	Carriers	% (95% CI)
Europe*
	Finnish	289	61	21·1% (16·5–26·3)	48	9	18·8% (8·9–32·6)
	Swedish	..	..	..	6	0	0% (0·0–45·9)
	English	916	62	6·8% (5·2–8·6)	543	31	5·7% (3·9–8·0)
	German	421	22	5·2% (3·3–7·8)	..	..	..
	Dutch	..	..	..	224	5	2·2% (0·7–5·1)
	French	..	..	..	150	14	9·3% (5·2–15·2)
	Italian	465	19	4·1% (2·5–6·3)	..	..	..
	Sardinian	129	10	7·8% (3·8–13·8)	10	0	0% (0·0–30·8)
	Moldovan	3	0	0% (0·0–70·8)	..	..	..
	Total (Europe)	2223	174	7·8% (6·7–9·0)	981	59	6·0% (4·6–7·7)
USA
	White	890	48	5·4% (4·0–7·1)	..	..	..
	Hispanic	72	6	8·3% (3·1–17·3)	..	..	..
	Black	49	2	4·1% (0·5–14·0)	..	..	..
	Native American	3	0	0% (0·0–70·8)	..	..	..
	Total (USA)	1014	56	5·5% (4·2–7·1)	..	..	..
Rest of the world
	Middle Eastern*	1	0	0% (0·0–97·5)	..	..	..
	Indian	31	0	0% (0·0–11·2)	31	0	0% (0·0–11·2)
	Asian	238	0	0% (0·0–1·5)	10	0	0% (0·0–30·8)
	Pacific Islander/Guam	90	0	0% (0·0–4·0)	..	..	..
	Australian*	263	14	5·3% (2·9–8·8)	..	..	..
Overall		3860	244	6·3% (5·6–7·1)	1022	59	5·8% (4·4–7·4)

Data for Finnish (289 with ALS and 48 with FTD), English (333 with FTD), and Dutch (224 with FTD) patients were previously published,^{10, 11, 12} but are included here to establish global frequencies. ALS=amyotrophic lateral sclerosis. FTD=frontotemporal dementia.

^*All self-reported as white.