| 1. |
- Olafsson, S, et al.
(författare)
-
Fourteen sequence variants that associate with multiple sclerosis discovered by meta-analysis informed by genetic correlations
- 2017
-
Ingår i: NPJ genomic medicine. - : Springer Science and Business Media LLC. - 2056-7944. ; 2, s. 24-
-
Tidskriftsartikel (refereegranskat)abstract
- A meta-analysis of publicly available summary statistics on multiple sclerosis combined with three Nordic multiple sclerosis cohorts (21,079 cases, 371,198 controls) revealed seven sequence variants associating with multiple sclerosis, not reported previously. Using polygenic risk scores based on public summary statistics of variants outside the major histocompatibility complex region we quantified genetic overlap between common autoimmune diseases in Icelanders and identified disease clusters characterized by autoantibody presence/absence. As multiple sclerosis-polygenic risk scores captures the risk of primary biliary cirrhosis and vice versa (P = 1.6 × 10−7, 4.3 × 10−9) we used primary biliary cirrhosis as a proxy-phenotype for multiple sclerosis, the idea being that variants conferring risk of primary biliary cirrhosis have a prior probability of conferring risk of multiple sclerosis. We tested 255 variants forming the primary biliary cirrhosis-polygenic risk score and found seven multiple sclerosis-associating variants not correlated with any previously established multiple sclerosis variants. Most of the variants discovered are close to or within immune-related genes. One is a low-frequency missense variant in TYK2, another is a missense variant in MTHFR that reduces the function of the encoded enzyme affecting methionine metabolism, reported to be dysregulated in multiple sclerosis brain.
|
|
| 2. |
|
|
| 3. |
- Thorgeirsson, T. E., et al.
(författare)
-
A rare missense mutation in CHRNA4 associates with smoking behavior and its consequences
- 2016
-
Ingår i: Molecular Psychiatry. - : Springer Science and Business Media LLC. - 1359-4184 .- 1476-5578. ; 21:5, s. 594-600
-
Tidskriftsartikel (refereegranskat)abstract
- Using Icelandic whole-genome sequence data and an imputation approach we searched for rare sequence variants in CHRNA4 and tested them for association with nicotine dependence. We show that carriers of a rare missense variant (allele frequency = 0.24%) within CHRNA4, encoding an R336C substitution, have greater risk of nicotine addiction than non-carriers as assessed by the Fagerstrom Test for Nicotine Dependence (P = 1.2 x 10(-4)). The variant also confers risk of several serious smoking-related diseases previously shown to be associated with the D398N substitution in CHRNA5. We observed odds ratios (ORs) of 1.7-2.3 for lung cancer (LC; P = 4.0 x 10(-4)), chronic obstructive pulmonary disease (COPD; P = 9.3 x 10(-4)), peripheral artery disease (PAD; P = 0.090) and abdominal aortic aneurysms (AAAs; P = 0.12), and the variant associates strongly with the early-onset forms of LC (OR = 4.49, P = 2.2 x 10(-4)), COPD (OR = 3.22, P = 2.9 x 10(-4)), PAD (OR = 3.47, P = 9.2 x 10(-3)) and AAA (OR = 6.44, P = 6.3 x 10(-3)). Joint analysis of the four smoking-related diseases reveals significant association (P = 6.8 x 10(-5)), particularly for early-onset cases (P = 2.1 x 10(-7)). Our results are in agreement with functional studies showing that the human alpha 4 beta 2 isoform of the channel containing R336C has less sensitivity for its agonists than the wild-type form following nicotine incubation.
|
|
| 4. |
|
|
| 5. |
|
|
| 6. |
|
|
| 7. |
|
|
| 8. |
|
|
| 9. |
|
|
| 10. |
|
|
