| 1. |
|
|
| 2. |
|
|
| 3. |
- Bergholdt, R., et al.
(author)
-
No association of the IRS1 and PAX4 genes with type I diabetes
- 2009
-
In: Genes and Immunity. - : Springer Science and Business Media LLC. - 1476-5470 .- 1466-4879. ; 10, s. 49-53
-
Journal article (peer-reviewed)abstract
- To reassess earlier suggested type I diabetes (T1D) associations of the insulin receptor substrate 1 (IRS1) and the paired domain 4 gene (PAX4) genes, the Type I Diabetes Genetics Consortium (T1DGC) evaluated single-nucleotide polymorphisms (SNPs) covering the two genomic regions. Sixteen SNPs were evaluated for IRS1 and 10 for PAX4. Both genes are biological candidate genes for T1D. Genotyping was performed in 2300 T1D families on both Illumina and Sequenom genotyping platforms. Data quality and concordance between the platforms were assessed for each SNP. Transmission disequilibrium testing neither show T1D association of SNPs in the two genes, nor did haplotype analysis. In conclusion, the earlier suggested associations of IRS1 and PAX4 to T1D were not supported, suggesting that they may have been false positive results. This highlights the importance of thorough quality control, selection of tagging SNPs, more than one genotyping platform in high throughput studies, and sufficient power to draw solid conclusions in genetic studies of human complex diseases. Genes and Immunity (2009) 10, S49-S53; doi:10.1038/gene.2009.91
|
|
| 4. |
- Concannon, P, et al.
(author)
-
Type 1 Diabetes: Evidence for susceptibility loci from four genome-wide linkage scans in 1,435 multiplex families.
- 2005
-
In: Diabetes. - 1939-327X. ; 54, s. 2995-3001
-
Journal article (peer-reviewed)abstract
- Type 1 diabetes is a common, multifactorial disease with strong familial clustering (genetic risk ratio [{lambda}S] ~ 15). Approximately 40% of the familial aggregation of type 1 diabetes can be attributed to allelic variation of HLA loci in the major histocompatibility complex on chromosome 6p21 (locus-specific {lambda}S ~ 3). Three other disease susceptibility loci have been clearly demonstrated based on their direct effect on risk, INS (chromosome 11p15, allelic odds ratio [OR] ~ 1.9), CTLA4 (chromosome 2q33, allelic OR ~ 1.2), and PTPN22 (chromosome 1p13, allelic OR ~ 1.7). However, a large proportion of type 1 diabetes clustering remains unexplained. We report here on a combined linkage analysis of four datasets, three previously published genome scans, and one new genome scan of 254 families, which were consolidated through an international consortium for type 1 diabetes genetic studies (www.t1dgc.org) and provided a total sample of 1,435 families with 1,636 affected sibpairs. In addition to the HLA region (nominal P = 2.0 x 10–52), nine non–HLA-linked regions showed some evidence of linkage to type 1 diabetes (nominal P < 0.01), including three at (or near) genome-wide significance (P < 0.05): 2q31-q33, 10p14-q11, and 16q22-q24. In addition, after taking into account the linkage at the 6p21 (HLA) region, there was evidence supporting linkage for the 6q21 region (empiric P < 10–4). More than 80% of the genome could be excluded as harboring type 1 diabetes susceptibility genes of modest effect ({lambda}S ≥ 1.3) that could be detected by linkage. This study represents one of the largest linkage studies ever performed for any common disease. The results demonstrate some consistency emerging for the existence of susceptibility loci on chromosomes 2q31-q33, 6q21, 10p14-q11, and 16q22-q24 but diminished support for some previously reported locations.
|
|
| 5. |
- Wills, A-M, et al.
(author)
-
A large-scale international meta-analysis of paraoxonase gene polymorphisms in sporadic ALS.
- 2009
-
In: Neurology. - : American Academy of Neurology. - 0028-3878 .- 1526-632X. ; 73:1, s. 16-24
-
Journal article (peer-reviewed)abstract
- BACKGROUND: Six candidate gene studies report a genetic association of DNA variants within the paraoxonase locus with sporadic amyotrophic lateral sclerosis (ALS). However, several other large studies, including five genome-wide association studies, have not duplicated this finding. METHODS: We conducted a meta-analysis of 10 published studies and one unpublished study of the paraoxonase locus, encompassing 4,037 ALS cases and 4,609 controls, including genome-wide association data from 2,018 ALS cases and 2,425 controls. RESULTS: The combined fixed effects odds ratio (OR) for rs662 (PON1 Q192R) was 1.09 (95% confidence interval [CI], 1.02-1.16, p = 0.01); the genotypic OR for RR homozygotes at Q192R was 1.25 (95% CI, 1.07-1.45, p = 0.0004); the combined OR for rs854560 (PON1 L55M) was 0.97 (95% CI, 0.86-1.10, p = 0.62); the OR for rs10487132 (PON2) was 1.08 (95% CI, 0.92-1.27, p = 0.35). Although the rs662 polymorphism reached a nominal level of significance, no polymorphism was significant after multiple testing correction. In the subanalysis of samples with genome-wide data from which population outliers were removed, rs662 had an OR of 1.06 (95% CI, 0.97-1.16, p = 0.22). CONCLUSIONS: In contrast to previous positive smaller studies, our genetic meta-analysis showed no significant association of amyotrophic lateral sclerosis (ALS) with the PON locus. This is the largest meta-analysis of a candidate gene in ALS to date and the first ALS meta-analysis to include data from whole genome association studies. The findings reinforce the need for much larger and more collaborative investigations of the genetic determinants of ALS.
|
|
