The genomics of preterm birth: from animal models to human studies

Peer reviewe

Genetic and observational evidence : No independent role for cholesterol efflux over static high-density lipoprotein concentration measures in coronary heart disease risk assessment

Background Observational findings for high-density lipoprotein (HDL)-mediated cholesterol efflux capacity (HDL-CEC) and coronary heart disease (CHD) appear inconsistent, and knowledge of the genetic architecture of HDL-CEC is limited. Objectives A large-scale observational study on the associations of HDL-CEC and other HDL-related measures with CHD and the largest genome-wide association study (GWAS) of HDL-CEC. Participants/methods Six independent cohorts were included with follow-up data for 14,438 participants to investigate the associations of HDL-related measures with incident CHD (1,570 events). The GWAS of HDL-CEC was carried out in 20,372 participants. Results HDL-CEC did not associate with CHD when adjusted for traditional risk factors and HDL cholesterol (HDL-C). In contradiction, almost all HDL-related concentration measures associated consistently with CHD after corresponding adjustments. There were no genetic loci associated with HDL-CEC independent of HDL-C and triglycerides. Conclusion HDL-CEC is not unequivocally associated with CHD in contrast to HDL-C, apolipoprotein A-I, and most of the HDL subclass particle concentrations.Peer reviewe

Haplotype of the Interleukin 17A gene is associated with osteitis after Bacillus Calmette-Guerin vaccination

Bacillus Calmette-Guerin (BCG) osteitis was more common in Finland than elsewhere at the time when universal BCG vaccinations were given to Finnish newborns. There is evidence that IL-17 plays a role in the defense against tuberculosis. The aim of this study was to evaluate the associations of IL17A rs4711998, IL17A rs8193036 and IL17A rs2275913 single-nucleotide polymorphisms (SNPs) with the risk of BCG osteitis after newborn vaccination. IL17A rs4711998, rs8193036 and rs2275913 SNPs were determined in 131 adults had presented with BCG osteitis after newborn BCG vaccination. We analyzed, using the HaploView and PLINK programs, whether allele or haplotype frequencies of these SNPs differ between the former BCG osteitis patients and Finnish population controls. Of the three IL17A SNPs studied, rs4711998 associated nominally with BCG osteitis; minor allele frequency was 0.215 in 130 BCG osteitis cases and 0.298 in 99 controls (p = 0.034). Frequency of the second common haplotype (GTA) differed significantly between BCG osteitis cases and controls (0.296 vs. 0.184, p = 0.040 after multi-testing correction). The GTA haplotype of the IL17A SNPs rs4711998, rs8193036 and rs2275913 was associated with osteitis after BCG vaccination

A Potential Novel Spontaneous Preterm Birth Gene, AR, Identified by Linkage and Association Analysis of X Chromosomal Markers

Peer reviewe

Expression of CPPED1 in human trophoblasts is associated with timing of term birth

Understanding of timing of human parturition is incomplete. Therefore, we carried out proteomic analyses of full-term placentas from uncomplicated pregnancies to identify protein signatures associated with the onset of spontaneous delivery. We found quantitative associations of 10 proteins with spontaneous term birth, evident either in the basal or in the chorionic plates or in both. Additional 18 proteins were associated according to the location within placenta indicating local variations in protein amounts. Calcineurin-like phosphoesterase domain-containing 1 (CPPED1), a phosphatase previously suggested dephosphorylating AKT1/PKB, was one of the identified proteins. qRT-PCR revealed the mRNA level of CPPED1 was higher in elective caesarean deliveries than in spontaneous births, while immunohistochemistry showed CPPED1 in cytotrophoblasts, syncytiotrophoblasts and extravillous trophoblasts. Noteworthy, phosphorylation status of AKT1 did not differ between placentas from elective caesarean and spontaneous deliveries. Additionally, analyses of samples from infants indicated that single-nucleotide polymorphisms rs11643593 and rs8048866 of CPPED1 were associated with duration of term pregnancy. Finally, post-transcriptional silencing of CPPED1 in cultured HTR8/SVneo cells by siRNAs affected gene expression in pathways associated with inflammation and blood vessel development. We postulate that functions regulated by CPPED1 in trophoblasts at choriodecidual interphase have a role in the induction of term labour, but it may be independent of AKT1

Genome-wide association study of polymorphisms predisposing to bronchiolitis

Bronchiolitis is a major cause of hospitalization among infants. Severe bronchiolitis is associated withlater asthma, suggesting a common genetic predisposition. Genetic background of bronchiolitis is notwell characterized. To identify polymorphisms associated with bronchiolitis, we conducted a genomewideassociation study (GWAS) in which 5,300,000 single nucleotide polymorphisms (SNPs) were testedfor association in a Finnish–Swedish population of 217 children hospitalized for bronchiolitis and 778controls. The most promising SNPs (n = 77) were genotyped in a Dutch replication population of 416cases and 432 controls. Finally, we used a set of 202 Finnish bronchiolitis cases to further investigatecandidate SNPs. We did not detect genome-wide significant associations, but several suggestiveassociation signals (p were nominally associated (p (eQTL) for KCND3, previously shown to be associated with occupational asthma. In the additionalset of Finnish cases, the association for another SNP (rs9591920) within a noncoding RNA locus wasfurther strengthened. Our results provide a first genome-wide examination of the genetics underlyingbronchiolitis. These preliminary findings require further validation in a larger sample size.</p

A study of genes encoding cytokines (IL6, IL10, TNF), cytokine receptors (IL6R, IL6ST), and glucocorticoid receptor (NR3C1) and susceptibility to bronchopulmonary dysplasia

Peer reviewe

Mapping a New Spontaneous Preterm Birth Susceptibility Gene, IGF1R, Using Linkage, Haplotype Sharing, and Association Analysis

Peer reviewe

Genetic and observational evidence: No independent role for cholesterol efflux over static high-density lipoprotein concentration measures in coronary heart disease risk assessment

Background Observational findings for high-density lipoprotein (HDL)-mediated cholesterol efflux capacity (HDL-CEC) and coronary heart disease (CHD) appear inconsistent, and knowledge of the genetic architecture of HDL-CEC is limited. Objectives A large-scale observational study on the associations of HDL-CEC and other HDL-related measures with CHD and the largest genome-wide association study (GWAS) of HDL-CEC. Participants/methods Six independent cohorts were included with follow-up data for 14,438 participants to investigate the associations of HDL-related measures with incident CHD (1,570 events). The GWAS of HDL-CEC was carried out in 20,372 participants. Results HDL-CEC did not associate with CHD when adjusted for traditional risk factors and HDL cholesterol (HDL-C). In contradiction, almost all HDL-related concentration measures associated consistently with CHD after corresponding adjustments. There were no genetic loci associated with HDL-CEC independent of HDL-C and triglycerides. Conclusion HDL-CEC is not unequivocally associated with CHD in contrast to HDL-C, apolipoprotein A-I, and most of the HDL subclass particle concentrations.</p

Apolipoprotein A-I concentrations and risk of coronary artery disease: A Mendelian randomization study

Background and aimsApolipoprotein A-I (apoA-I) infusions represent a potential novel therapeutic approach for the prevention of coronary artery disease (CAD). Although circulating apoA-I concentrations inversely associate with risk of CAD, the evidence base of this representing a causal relationship is lacking. The aim was to assess the causal role of apoA-I using human genetics.MethodsWe identified a variant (rs12225230) in APOA1 locus that associated with circulating apoA-I concentrations (p ResultsApoA-I was associated with a lower risk of CAD in observational analyses (HR 0.81; 95%CI: 0.75, 0.88; per 1-SD higher apoA-I), with the association showing a dose-response relationship. Rs12225230 associated with apoA-I concentrations (per-C allele beta 0.076 SD; SE: 0.013; p = 1.5 × 10−9) but not with confounders. In Mendelian randomization analyses, apoA-I was not related to risk of CAD (OR 1.13; 95%CI: 0.98,1.30 per 1-SD higher apoA-I), which was different from the observational association. Similar findings were observed using an independent ABCA1 variant in sensitivity analysis.ConclusionsGenetic evidence fails to support a cardioprotective role for apoA-I. This is in line with the cumulative evidence showing that HDL-related phenotypes are unlikely to have a protective role in CAD.</div