@article {1335, title = {The association of genetic variants in interleukin-1 genes with cognition: findings from the cardiovascular health study.}, journal = {Exp Gerontol}, volume = {46}, year = {2011}, month = {2011 Dec}, pages = {1010-9}, abstract = {

The inflammatory cytokine interleukin-1 (IL1) potentially plays a role in cognitive deterioration through pathology due to a dementing disorder or due to an aging process. Study of genetic variants in the IL1 genes has been mostly limited to diseases such as Alzheimer{\textquoteright}s, however, there may be benefit to studying a continuous measure of cognition. Using data from the Cardiovascular Health Study, we evaluate genetic variation in the genes encoding inflammatory agonists IL1A and IL1B, and the antagonist IL1RN, with repeated measures of global cognition (3MS) and processing speed (DSST), using mixed effects models. We found statistically significant minor allele SNP associations with baseline performance on the 3MS in the IL1RN gene for Caucasians (rs17042917: beta=0.47, 95\%CI=0.09, 0.85, p=0.016; rs4251961: beta=-0.36, 95\%CI=-0.13,-0.60, p=0.0027; rs931471: beta=0.39, 95\%CI=0.13, 0.65, p=0.0032), and the IL1B gene for African Americans (rs1143627: beta=1.6, 95\%CI=0.48, 2.8; p=0.006 and rs1143634: beta=2.09, 95\%CI=0.39, 3.8; p=0.016). Associations appear to be weaker in a subgroup with higher education level. Upon removing those diagnosed with dementia, effect sizes and statistical significance attenuated. These results provide supporting evidence that genetic variants in IL1 genes may be involved in inflammatory-related lowered cognition, that higher education may modify genetic predisposition, and that these associations may be driven by a dementia process.

}, keywords = {African Americans, Aged, Aged, 80 and over, Cognition, Cognition Disorders, Dementia, Educational Status, European Continental Ancestry Group, Female, Genetic Predisposition to Disease, Genetic Variation, Genotype, Humans, Interleukin 1 Receptor Antagonist Protein, Interleukin-1alpha, Interleukin-1beta, Linkage Disequilibrium, Longitudinal Studies, Male, Polymorphism, Single Nucleotide, Prospective Studies, Risk Factors, United States}, issn = {1873-6815}, doi = {10.1016/j.exger.2011.09.005}, author = {Benke, K S and Carlson, M C and Doan, B Q and Walston, J D and Xue, Q L and Reiner, A P and Fried, L P and Arking, D E and Chakravarti, A and Fallin, M D} } @article {6133, title = {Novel gene variants predict serum levels of the cytokines IL-18 and IL-1ra in older adults.}, journal = {Cytokine}, volume = {65}, year = {2014}, month = {2014 Jan}, pages = {10-6}, abstract = {

Activation of inflammatory pathways measured by serum inflammatory markers such as interleukin-18 (IL-18) and interleukin-1 receptor antagonist (IL-1ra) is strongly associated with the progression of chronic disease states in older adults. Given that these serum cytokine levels are in part a heritable trait, genetic variation may predict increased serum levels. Using the Cardiovascular Health Study and InCHIANTI cohorts, a genome-wide association study was performed to identify genetic variants that influence IL-18 and IL-1ra serum levels among older adults. Multiple linear regression models characterized the association between each SNP and log-transformed cytokine values. Tests for multiple independent signals within statistically significant loci were performed using haplotype analysis and regression models conditional on lead SNP in each region. Multiple SNPs were associated with these cytokines with genome-wide significance, including SNPs in the IL-18-BCO gene region of chromosome 2 for IL-18 (top SNP rs2250417, P=1.9{\texttimes}10(-32)) and in the IL-1 gene family region of chromosome 2 for IL-1ra (rs6743376, P=2.3{\texttimes}10(-26)). Haplotype tests and conditional linear regression models showed evidence of multiple independent signals in these regions. Serum IL-18 levels were also associated with a region on chromosome 2 containing the NLRC4 gene (rs12989936, P=2.7{\texttimes}10(-19)). These data characterize multiple robust genetic signals that influence IL-18 and IL-1ra cytokine production. In particular, the signal for serum IL-18 located on chromosome two is novel and potentially important in inflammasome triggered chronic activation of inflammation in older adults. Replication in independent cohorts is an important next step, as well as molecular studies to better understand the role of NLRC4.

}, keywords = {Aged, Aged, 80 and over, Calcium-Binding Proteins, CARD Signaling Adaptor Proteins, Chromosomes, Human, Pair 2, Female, Genetic Variation, Genome-Wide Association Study, Genotype, Haplotypes, Humans, Inflammation, Interleukin 1 Receptor Antagonist Protein, Interleukin-18, Male, Polymorphism, Single Nucleotide}, issn = {1096-0023}, doi = {10.1016/j.cyto.2013.10.002}, author = {Matteini, A M and Li, J and Lange, E M and Tanaka, T and Lange, L A and Tracy, R P and Wang, Y and Biggs, M L and Arking, D E and Fallin, M D and Chakravarti, A and Psaty, B M and Bandinelli, S and Ferrucci, L and Reiner, A P and Walston, J D} } @article {7599, title = {Generalization and fine mapping of European ancestry-based central adiposity variants in African ancestry populations.}, journal = {Int J Obes (Lond)}, volume = {41}, year = {2017}, month = {2017 Feb}, pages = {324-331}, abstract = {

BACKGROUND/OBJECTIVES: Central adiposity measures such as waist circumference (WC) and waist-to-hip ratio (WHR) are associated with cardiometabolic disorders independently of body mass index (BMI) and are gaining clinically utility. Several studies report genetic variants associated with central adiposity, but most utilize only European ancestry populations. Understanding whether the genetic associations discovered among mainly European descendants are shared with African ancestry populations will help elucidate the biological underpinnings of abdominal fat deposition.

SUBJECTS/METHODS: To identify the underlying functional genetic determinants of body fat distribution, we conducted an array-wide association meta-analysis among persons of African ancestry across seven studies/consortia participating in the Population Architecture using Genomics and Epidemiology (PAGE) consortium. We used the Metabochip array, designed for fine-mapping cardiovascular-associated loci, to explore novel array-wide associations with WC and WHR among 15 945 African descendants using all and sex-stratified groups. We further interrogated 17 known WHR regions for African ancestry-specific variants.

RESULTS: Of the 17 WHR loci, eight single-nucleotide polymorphisms (SNPs) located in four loci were replicated in the sex-combined or sex-stratified meta-analyses. Two of these eight independently associated with WHR after conditioning on the known variant in European descendants (rs12096179 in TBX15-WARS2 and rs2059092 in ADAMTS9). In the fine-mapping assessment, the putative functional region was reduced across all four loci but to varying degrees (average 40\% drop in number of putative SNPs and 20\% drop in genomic region). Similar to previous studies, the significant SNPs in the female-stratified analysis were stronger than the significant SNPs from the sex-combined analysis. No novel associations were detected in the array-wide analyses.

CONCLUSIONS: Of 17 previously identified loci, four loci replicated in the African ancestry populations of this study. Utilizing different linkage disequilibrium patterns observed between European and African ancestries, we narrowed the suggestive region containing causative variants for all four loci.

}, issn = {1476-5497}, doi = {10.1038/ijo.2016.207}, author = {Yoneyama, S and Yao, J and Guo, X and Fernandez-Rhodes, L and Lim, U and Boston, J and B{\r u}{\v z}kov{\'a}, P and Carlson, C S and Cheng, I and Cochran, B and Cooper, R and Ehret, G and Fornage, M and Gong, J and Gross, M and Gu, C C and Haessler, J and Haiman, C A and Henderson, B and Hindorff, L A and Houston, D and Irvin, M R and Jackson, R and Kuller, L and Leppert, M and Lewis, C E and Li, R and Le Marchand, L and Matise, T C and Nguyen, K-Dh and Chakravarti, A and Pankow, J S and Pankratz, N and Pooler, L and Ritchie, M D and Bien, S A and Wassel, C L and Chen, Y-DI and Taylor, K D and Allison, M and Rotter, J I and Schreiner, P J and Schumacher, F and Wilkens, L and Boerwinkle, E and Kooperberg, C and Peters, U and Buyske, S and Graff, M and North, K E} }