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The authors evaluated the contributions of nine genetic (G) variants (selected from 275 single nucleotide polymorphisms in 11 reverse cholesterol transport pathway genes), five environmental (E) factors (selected from 10), and G × G, E × E, and G × E interactions in explaining population variance of blood lipid concentrations. Total cholesterol, triglycerides, and high density lipoprotein (HDL) cholesterol were measured, and low density lipoprotein (LDL) cholesterol and HDL cholesterol/LDL cholesterol ratio were calculated in a population-based random sample of 1,543 men and women in Geneva, Switzerland, aged 35-74 years in 1999-2001. Explained variances (R2) for HDL cholesterol/LDL cholesterol ratio, HDL cholesterol, and LDL cholesterol, respectively, were 34%, 33%, and 19%, decomposed into main effects of G (6%, 4%, and 5%) and E (25%, 28%, and 11%), with just 3%, 2%, and 3% due to G × G, E × E, and G × E interactions, respectively. Risk factor clustering was only moderate: 70% of study subjects had ≤3 variants, 75% had ≤2 environmental exposures, and 69% had ≤5 of both types of factors. Multiple genes with weak associations, together with more dominating environmental factors, are involved in determining blood lipid concentrations. Interactions added little explained variance. Increasing trends in hypercholesterolemia are attributable to environmental changes affecting populations as a whole. Reducing obesity and smoking and moderating alcohol intake in entire populations should remain the primary strategies for lipid control

This study explored the genetic basis of the combination of extreme blood levels of HDL-C and LDL-C, a well-studied endophenotype for CVD, which has several attractive features as a target for genetic analysis: (1) the trait is moderately heritable; (2) non-genetic risk factors account for a significant but still limited portion of the phenotypic variance; (3) it is known to be moderated by a number of gene products. We exhaustively surveyed 11 candidate genes for allelic variation in a random population-based sample characterized for known CVD risk factors and blood lipid profiles. With the goal of generating specific etiological hypotheses, we compared two groups of subjects with extreme lipid phenotypes, from the same source population, using a case-control design. Cases (n=186) were subjects, within the total sample of 1708 people, who scored in the upper tertile of LDL-C and the lowest tertile of HDL-C, while controls (n=185) scored in the lowest tertile of LDL-C and the upper tertile of HDL-C. We used logistic regression and a four-tiered, systematic model building strategy with internal cross-validation and bootstrapping to investigate the relationships between the trait and 275 genetic variants in the presence of 10 non-genetic risk factors. Our results implicate a subset of nine genetic variants, spanning seven candidate genes, together with five environmental risk factors, in the etiology of extreme lipoprotein phenotypes. We propose a model involving these 14 genetic and non-genetic risk factors for evaluation in future independent studies

The Medieval Review, (dlps) baj9928.0503.008, (tmr) 05.03.08, http://quod.lib.umich.edu/t/text/accesspolicy.html

In 1995, superintendents and school board members from K-12 school districts in Nebraska were surveyed to determine the influence of financial/economic, social/political, demographic, and education/instruction factors on their attitudes toward school district consolidation in Nebraska. Data were collected from 251 superintendents and 198 school board members by means of a written survey developed by the researcher. Mean scores, dependent t-test, Analysis of Variance, Stepwise Multiple Regression and Multivariate Analysis of Variance were used to analyze the eleven research questions in the study. Based on the statistical treatment, the following conclusions appear warranted: (1) Superintendents and school board members agree somewhat that more school district consolidation should occur across the state. (2) As compared to their attitude toward statewide consolidation, superintendents and school board members are significantly less in favor of consolidation involving their own district, which indicates that support for consolidation decreases as it is applied at the local district level. (3) Superintendents are more supportive than are school board members of school district consolidation occurring across the state and consolidation involving their local district. (4) Superintendents perceive the financial/economic and demographic factors as more important influences on school district consolidation than did school board members. School board members perceive the social/political and education/instruction factors as more important influences on consolidation than did superintendents. (5) The more respondents agree with the education/instruction and social/political factors, the less they are in favor of consolidation taking place across the state and at the local district level. (6) The more respondents agree with the financial/economic factor, the more likely they are to favor school district consolidation taking place across the state and at the local district leve