This study suggests that the prevalence of a cluster of cardiovascular risk factors relates to background exposure to a mixture of POPs, several of which are also related to the prevalence of diabetes. POPs associated differentially with different components of the metabolic syndrome.

Aims/hypothesis We examined the cross-sectional and longitudinal relationships between C-reactive protein (CRP), a marker of low-grade inflammation, and insulin resistance and whether the association was independent of obesity and oxidative stress. Methods CRP and insulin resistance (homeostasis model assessment of insulin resistance [HOMA-IR]) data were obtained in a population-based, prospective observational study, Coronary Artery Risk Development in Young Adults (CARDIA), during 1992–2006. Results CRP showed a significant positive association with insulin resistance, both cross-sectionally and longitudinally (5 year follow-up). The estimated increment in HOMA-IR was 0.34 loge(pmol/l×[mmol/l]/156.25) (p value for trend <0.0001) in the highest vs lowest CRP quartiles in cross-sectional analysis, whereas the corresponding estimate was 0.12 (p trend <0.0001) in the highest vs lowest CRP quartiles longitudinally over 5 years. The gradient of HOMA-IR across CRP was attenuated but remained statistically significant after controlling for body fat measurements (0.06 in the highest vs lowest CRP in both cross-sectional [p value for trend=0.001] and longitudinal analyses [p value for trend=0.01]), and was little changed by further adjustment for oxidative stress markers (F2-isoprostanes and oxidised LDL). There were consistent increments in the levels of HOMA-IR with increasing concentrations of CRP over time. In contrast, higher HOMA-IR did not predict future increases in CRP. Findings were similar using fibrinogen as the predictor variable. Conclusions/interpretation Although a substantial portion of this association was explained by obesity, CRP was independently related to concurrent and future insulin resistance.

Epidemiological studies have suggested a link between exposure to persistent organic pollutants (POPs) and hypertension. Cross-sectional associations of serum POP concentrations with the prevalence of newly diagnosed hypertension were investigated in 524 adult participants aged >/=40 years in the National Health and Nutrition Examination Survey 1999-2002. Twenty-one POPs (three polychlorinated dibenzo-p-dioxins (PCDDs), three polychlorinated dibenzofurans (PCDFs), five dioxin-like polychlorinated biphenyls (PCBs), six dioxin-unlike PCBs and four organochlorine (OC) pesticides) were selected because they were detectable in > or =60% of participants. Serum concentrations of PCDDs and PCDFs were associated with prevalent but newly diagnosed hypertension among women, but not among men. Across quartiles of the sum of category numbers of the three PCDDs and the three PCDFs, adjusted odds ratios in women were 1.0, 4.2 (95% confidence interval (CI): 1.0-17.1), 4.5 (1.0-19.9) and 5.0 (1.2-21.5) (P for trend=0.08) and 1.0, 2.6 (0.8-9.0), 5.9 (1.7-20.0) and 4.2 (1.3-14.3) (P for trend=0.01), respectively. On the other hand, PCBs tended toward positive association with hypertension only among men. Adjusted odds ratios in men in the highest quartiles of the sum of category numbers of the dioxin-like and non-dioxin-like PCBs were 2.3 (0.8-6.6) and 2.8 (0.9-8.5) (P for trend=0.11 or 0.04), respectively. OC pesticides were not clearly associated with hypertension in either gender. Hypertension had gender-specific associations with serum concentrations of some POPs. Considering the common presence of exposure to POPs in the general population, these findings need to be clarified in prospective studies.

Effective population size (Ne) is an important measure to understand population structure and genetic variability in animal species. The objective of this study was to estimate Ne in Sapsaree dogs using the information of rate of inbreeding and genomic data that were obtained from pedigree and the Illumina CanineSNP20 (20K) and CanineHD (170K) beadchips, respectively. Three SNP panels, i.e. Sap134 (20K), Sap60 (170K), and Sap183 (the combined panel from the 20K and 170K), were used to genotype 134, 60, and 183 animal samples, respectively. The Ne estimates based on inbreeding rate ranged from 16 to 51 about five to 13 generations ago. With the use of SNP genotypes, two methods were applied for Ne estimation, i.e. pair-wise r2 values using a simple expectation of distance and r2 values under a non-linear regression with respective distances assuming a finite population size. The average pair-wise Ne estimates across generations using the pairs of SNPs that were located within 5 Mb in the Sap134, Sap60, and Sap183 panels, were 1,486, 1,025 and 1,293, respectively. Under the non-linear regression method, the average Ne estimates were 1,601, 528, and 1,129 for the respective panels. Also, the point estimates of past Ne at 5, 20, and 50 generations ago ranged between 64 to 75, 245 to 286, and 573 to 646, respectively, indicating a significant Ne reduction in the last several generations. These results suggest a strong necessity for minimizing inbreeding through the application of genomic selection or other breeding strategies to increase Ne, so as to maintain genetic variation and to avoid future bottlenecks in the Sapsaree population.

The purpose of this study was to characterize genetic architecture of behavior patterns in Sapsaree dogs. The breed population (n = 8,256) has been constructed since 1990 over 12 generations and managed at the Sapsaree Breeding Research Institute, Gyeongsan, Korea. Seven behavioral traits were investigated for 882 individuals. The traits were classified as a quantitative or a categorical group, and heritabilities (h2) and variance components were estimated under the Animal model using ASREML 2.0 software program. In general, the h2 estimates of the traits ranged between 0.00 and 0.16. Strong genetic (rG) and phenotypic (rP) correlations were observed between nerve stability, affability and adaptability, i.e. 0.9 to 0.94 and 0.46 to 0.68, respectively. To detect significant single nucleotide polymorphism (SNP) for the behavioral traits, a total of 134 and 60 samples were genotyped using the Illumina 22K CanineSNP20 and 170K CanineHD bead chips, respectively. Two datasets comprising 60 (Sap60) and 183 (Sap183) samples were analyzed, respectively, of which the latter was based on the SNPs that were embedded on both the 22K and 170K chips. To perform genome-wide association analysis, each SNP was considered with the residuals of each phenotype that were adjusted for sex and year of birth as fixed effects. A least squares based single marker regression analysis was followed by a stepwise regression procedure for the significant SNPs (p<0.01), to determine a best set of SNPs for each trait. A total of 41 SNPs were detected with the Sap183 samples for the behavior traits. The significant SNPs need to be verified using other samples, so as to be utilized to improve behavior traits via marker-assisted selection in the Sapsaree population.