| 13464126 | Association of TOMM40 and SLC22A4 polymorphisms with ischemic stroke. | Yamase Y, etal., Biomed Rep. 2015 Jul;3(4):491-498. doi: 10.3892/br.2015.457. Epub 2015 Apr 29. | Recent genome-wide association studies (GWASs) and their meta-analyses have identified various genes and loci underlying the predisposition to ischemic stroke or coronary artery disease in Caucasian populations. Given that ischemic stroke and coronary artery disease may have a shared genetic archite cture, certain polymorphisms may confer genetic susceptibility to these two diseases. The aim of the present study was to examine the possible association of ischemic stroke with 29 single-nucleotide polymorphisms (SNPs) previously identified by the meta-analyses of GWASs as susceptibility loci for coronary artery disease. The study population comprised 3,187 Japanese individuals, including 894 subjects with ischemic stroke and 2,293 controls. The genotypes for the 29 SNPs of the 28 genes were determined by a method that combines the polymerase chain reaction and sequence-specific oligonucleotide probes with suspension array technology. Comparisons of the allele frequencies by the ¿2 test between subjects with ischemic stroke and controls revealed that rs9319428 (G->A) of the fms-related tyrosine kinase 1 gene (P=0.0471), rs2075650 (G->A) of the translocase of outer mitochondrial membrane 40 homolog gene (TOMM40, P=0.0102) and rs273909 (T->C) of the solute carrier family 22, member 4 gene (SLC22A4, P=0.0097) were significantly (P<0.05) associated with the prevalence of ischemic stroke. Multivariable logistic regression analysis with adjustment for age, gender, body mass index, smoking status and the prevalence of hypertension, diabetes mellitus and dyslipidemia revealed that rs2075650 of TOMM40 (P=0.0443; recessive model; odds ratio=0.50) and rs273909 of SLC22A4 (P=0.0123; dominant model; odds ratio=0.45) were significantly associated with ischemic stroke with the minor G and C allele, respectively, being protective against this condition. TOMM40 and SLC22A4 may thus be susceptibility loci for ischemic stroke in Japanese individuals. | 26171154 | 2015-07-01 |
| 13702117 | New Genetic Approaches to AD: Lessons from APOE-TOMM40 Phylogenetics. | Lutz MW, etal., Curr Neurol Neurosci Rep. 2016 May;16(5):48. doi: 10.1007/s11910-016-0643-8. | Clinical trials for Alzheimer's disease are now focusing on the earliest stages of the disease with the goal of delaying dementia onset. There is great utility in using genetic variants to identify individuals at high age-dependent risk when the goal is to begin treatment before the development of a ny cognitive symptoms. Genetic variants identified through large-scale genome-wide association studies have not substantially improved the accuracy provided by APOE genotype to identify people at high risk of late-onset Alzheimer's disease (LOAD). We describe novel approaches, focused on molecular phylogenetics, to finding genetic variants that predict age at LOAD onset with sufficient accuracy and precision to be useful. We highlight the discovery of a polymorphism in TOMM40 that, in addition to APOE, may improve risk prediction and review how TOMM40 genetic variants may impact the develop of LOAD independently from APOE. The analysis methods described in this review may be useful for other genetically complex human diseases. | 27039903 | 2016-05-01 |
| 11055863 | The effect of TOMM40 on spatial navigation in amnestic mild cognitive impairment. | Laczo J, etal., Neurobiol Aging. 2015 Jun;36(6):2024-33. doi: 10.1016/j.neurobiolaging.2015.03.004. Epub 2015 Mar 16. | The very long (VL) poly-T variant at rs10524523 ("523") of the TOMM40 gene may hasten the onset of late-onset Alzheimer's disease (LOAD) and induce more profound cognitive impairment compared with the short (S) poly-T variant. We examined the influence of TOMM40 style='font-weight:700;'>TOMM40 "523" polymorphism on spatial navigation and its brain structural correlates. Participants were apolipoprotein E (APOE) epsilon3/epsilon3 homozygotes with amnestic mild cognitive impairment (aMCI). The homozygotes were chosen because APOE epsilon3/epsilon3 variant is considered "neutral" with respect to LOAD risk. The participants were stratified according to poly-T length polymorphisms at "523" into homozygous for S (S/S; n = 16), homozygous for VL (VL/VL; n = 15) TOMM40 poly-T variant, and heterozygous (S/VL; n = 28) groups. Neuropsychological examination and testing in real-space human analog of the Morris Water Maze were administered. Both self-centered (egocentric) and world-centered (allocentric) spatial navigation was assessed. Brain magnetic resonance imaging scans were analyzed using FreeSurfer software. The S/S group, although similar to S/VL and VL/VL groups in demographic and neuropsychological profiles, performed better on allocentric navigation (p = 0.004) and allocentric delayed recall (p = 0.014), but not on egocentric navigation. Both S/VL and VL/VL groups had thinner right entorhinal cortex (p = 0.043) than the S/S group, whereas only the VL/VL group had thinner left entorhinal cortex (p = 0.043) and left posterior cingulate cortex (p = 0.024) than the S/S group. In conclusion, TOMM40 "523" VL variants are related to impairment in allocentric spatial navigation and reduced cortical thickness of specific brain regions among aMCI individuals with (LOAD neutral) APOE epsilon3/epsilon3 genotype. This may reflect a specific role of TOMM40 "523" in the pathogenesis of LOAD. | 25862420 | 2015-04-01 |
| 11553088 | APOE/TOMM40 genetic loci, white matter hyperintensities, and cerebral microbleeds. | Lyall DM, etal., Int J Stroke. 2015 Dec;10(8):1297-300. doi: 10.1111/ijs.12615. Epub 2015 Aug 26. | BACKGROUND: Two markers of cerebral small vessel disease are white matter hyperintensities and cerebral microbleeds, which commonly occur in people with Alzheimer's disease. AIM AND/OR HYPOTHESIS: To test for independent associations between two Alzheimer's disease-susceptibility gene loci--APOE ep silon and the TOMM40 '523' poly-T repeat--and white matter hyperintensities/cerebral microbleed burden in community-dwelling older adults. METHODS: Participants in the Lothian Birth Cohort 1936 underwent genotyping for APOE epsilon and TOMM40 523, and detailed structural brain magnetic resonance imaging at a mean age of 72.70 years (standard deviation = 0.7; range = 71-74). RESULTS: No significant effects of APOE epsilon or TOMM40 523 genotypes on white matter hyperintensities or cerebral microbleed burden were found amongst 624 participants. CONCLUSIONS: Lack of association between two Alzheimer's disease susceptibility gene loci and markers of cerebral small vessel disease may reflect the relative health of this population compared with those in other studies in the literature. | 26310205 | 2015-10-01 |
| 11574987 | A TOMM40 poly-T variant modulates gene expression and is associated with vocabulary ability and decline in nonpathologic aging. | Payton A, etal., Neurobiol Aging. 2016 Mar;39:217.e1-7. doi: 10.1016/j.neurobiolaging.2015.11.017. Epub 2015 Dec 8. | The Translocase of Outer Mitochondrial Membrane 40 Homolog and Apolipoprotein E (TOMM40-APOE) locus has been associated with a number of age-related phenotypes in humans including nonpathologic cognitive aging, late-onset Alzheimer's disease, and longevity. Here , we investigate the influence of the TOMM40 intron 6 poly-T variant (rs10524523) on TOMM40 gene expression and cognitive abilities and decline in a cohort of 1613 community-dwelling elderly volunteers who had been followed for changes in cognitive functioning over a period of 14 years (range = 12-18 years). We showed that the shorter length poly-T variants were found to act as a repressor of luciferase gene expression in reporter gene constructs. Expression was reduced to approximately half of that observed for the very long variant. We further observed that the shorter poly-T variant was significantly associated with reduced vocabulary ability and a slower rate of vocabulary decline with age compared to the very long poly-T variants. No significant associations were observed for memory, fluid intelligence or processing speed, although the direction of effect, where the short variant was correlated with reduced ability and slower rate of decline was observed for all tests. Our results indicate that the poly-T variant has the ability to interact with transcription machinery and differentially modulate reporter gene expression and influence vocabulary ability and decline with age. | 26742953 | 2016-03-01 |
| 401799676 | Association between CETP, MLXIPL, and TOMM40 polymorphisms and serum lipid levels in a Latvian population. | Radovica I, etal., Meta Gene. 2014 Aug 20;2:565-78. doi: 10.1016/j.mgene.2014.07.006. eCollection 2014 Dec. | BACKGROUND: Abnormal lipid levels are considered one of the most significant risk factors for atherosclerosis and coronary artery disease, two of the main causes of death worldwide. Apart from monogenic cases of hypercholesterolemia, most of the common dyslipidemias are caused by a number of low-impact polymorphisms. It has recently been reported that frequent polymorphisms at a large number of loci are significantly associated with one or more blood lipid parameters in many populations. Identifying these associations in different populations and estimating the possible interactions between genetic models are necessary to explain the underlying genetic architecture of the associated loci and their ultimate impact on lipid-associated traits. METHODS: We estimated the association between 144 common single-nucleotide polymorphisms (SNPs) from published genome-wide association studies and the levels of total cholesterol, low- and high-density lipoprotein-cholesterol, and triglycerides in 1273 individuals from the Genome Database of the Latvian Population. We analyzed a panel of 144 common SNPs with Illumina GoldenGate Genotyping Assays on the Illumina BeadXpress System. RESULTS: Ten SNPs at the CETP locus and two at the MLXIPL locus were associated with reduced high-density lipoprotein-cholesterol levels; one SNP at the TOMM40 locus was associated with increased low-density lipoprotein-cholesterol; and four SNPs at the MLXIPL locus were associated with increased log triglyceride levels. There was also a significant correlation between the number of risk alleles and all the lipid parameters, suggesting that the coexistence of many low-impact SNPs has a greater effect on the dyslipidemia phenotype than the individual effects of found SNPs. CONCLUSION: We conclude that the CETP, MLXIPL, and TOMM40 loci are the strongest genetic factors underlying the variability in lipid traits in our population. | 25606439 | 2014-12-01 |
| 11052408 | The effects of an intronic polymorphism in TOMM40 and APOE genotypes in sporadic inclusion body myositis. | Gang Q, etal., Neurobiol Aging. 2015 Apr;36(4):1766.e1-3. doi: 10.1016/j.neurobiolaging.2014.12.039. Epub 2015 Jan 14. | A previous study showed that, in carriers of the apolipoprotein E (APOE) genotype epsilon3/epsilon3 or epsilon3/epsilon4, the presence of a very long (VL) polyT repeat allele in "translocase of outer mitochondrial membrane 40" (TOMM40) was less frequent in patie nts with sporadic inclusion body myositis (sIBM) compared with controls and associated with a later age of sIBM symptom onset, suggesting a protective effect of this haplotype. To further investigate the influence of these genetic factors in sIBM, we analyzed a large sIBM cohort of 158 cases as part of an International sIBM Genetics Study. No significant association was found between APOE or TOMM40 genotypes and the risk of developing sIBM. We found that the presence of at least 1 VL polyT repeat allele in TOMM40 was significantly associated with about 4 years later onset of sIBM symptoms. The age of onset was delayed by 5 years when the patients were also carriers of the APOE genotype epsilon3/epsilon3. In addition, males were likely to have a later age of onset than females. Therefore, the TOMM40 VL polyT repeat, although not influencing disease susceptibility, has a disease-modifying effect on sIBM, which can be enhanced by the APOE genotype epsilon3/epsilon3. | 25670332 | 2015-04-01 |