Table 2.
The association between C9orf72 expansion and ALS.
| Study group / Genotype |
No. Tested | Carriers of the C9orf72 expansion (30 repeats or more) |
Both alleles are less than 30 repeats |
p-value (Fisher's Exact test, df=1, two tailed) |
OR for heterozygous (95% CI, p-value of OR) |
|
|---|---|---|---|---|---|---|
| ALS patients: | AJ | 349 | 45a (12.9) | 304 (87.1) | p =2.04×10−18 | 44.26 (10.66–183.68, <0.0001) |
| MJ | 76 | 6 (7.9) | 70 (92.1) | p =0.0029 | 8.49 (2.07–34.76, 0.003) | |
| NAJ | 34 | 4b (11.8) | 30 (88.2) | p =0.0025 | 13.20 (2.82–61.78, 0.001) | |
| Total North Africa: MJ+NAJ | 110 | 10 (9.1) | 100 (90.9) | p =1.87×10−4 | 9.9 (2.67–36.69, 0.0006) | |
| Total (AJ, MJ, NAJ) | 459 | 55 (12.0) | 404 (88.0) | p =1.091×10−21 | 24.37 (9.68–61.33, <0.0001) | |
| Controlsc: | AJ | 600 | 2 (0.3) | 598 (99.7) | ||
| MJ | 300 | 3 (1.0) | 297 (99) | |||
| Total (AJ, MJ) | 900 | 5 (0.5) | 895 (99.5) | |||
a
One ALS patient had both alleles with more than 30 repeats.
b
One from Algier, one from Egypt, one from Tunis and one from Egypt/Tunis
c
Control groups are in Hardy-Weinberg equilibrium
Abbreviations: ALS= amyotrophic lateral sclerosis; CI= confidence interval; OR= odds ratio; AJ= Ashkenazi Jews; MJ= Moroccan Jews; NAJ= North Africa Jews that are not of Morocco descent.