Localization of genes for V+LDL plasma cholesterol levels on two diets in the opossum Monodelphis domestica

Prevalence of ABCB4 polymorphisms in gallstone disease in han-Chinese population

ATP Binding Cassette Transporter A4 (ABCB4) is a sterol export pump that regulates excretion of biliary cholesterol. We tested association between ABCB4 polymorphisms and gallstone disease using meta-analysis. In a cross-sectional study, 296 subjects were recruited from a hospital-based population. Total of 171 subjects were diagnosed as gallstone disease by abdominal ultrasonography from three cohort studies. We evaluated prevalence of ABCG8 rs11887534 (D19H) as a positive control, and the ABCB4 rs1202283 and rs2230028 polymorphisms on Chinese population were screened by meta-analysis and genotyped using TaqMan® SNP assay. Stata/SE 11.0 software and random-effects model were used in meta-analyzing 3 cohort between study heterogeneity. Four studies including three cohorts were used for final meta-analysis. In allelic model, minor alleles of ABCB4 rs1202283 (OR = 0.41, 95% CI: 0.25-0.67, P<0.001) and of ABCB4 rs2230028 (OR = 0.12, 95% CI: 0.06-0.22, P = 0.001) were associated with an increased risk for gallstone disease in Europeans. Funnel plot and Egger's test suggested absence of publication bias. Concentration of total cholesterol, low-density lipoprotein cholesterol (LDLC) (P = 0.015) and high-density lipoprotein cholesterol (HDLC) (P = 0.028) were significantly higher in subjects with gallstones disease than controls. ABCB4 rs1202283 (heterozygote AG) (P<0.0001), rs2230028 (heterozygote CT) (P = 0.023) and ABCG8 rs11887534 (heterozygote CG) (P = 0.006) were significantly associated with gallstone disease in Chinese population. Genetic risk associated with ABCB4 rs2230028 (homozygote GG) polymorphism was dominated in asymptomatic gallstone disease (95% C.I.: 0.219-0.768; P = 0.005). In conclusion, carriers of ABCB4 rs1202283, rs2230028 are at an increased risk for gallstone disease, while ABCB4 rs2230028 is associated with asymptomatic gallstone disease.

QTLs influencing carbohydrate and fat choice in a LOU/CxFischer 344 F2 rat population

OBJECTIVE

Individual differences in macronutrient selection, particularly fat and carbohydrate, and associated body weight gain are partly inherited as polygenic traits, but the potential genetic pathways are unknown. To give an overview of the Quantitative Trait Loci (QTLs) and candidate gene pathways influencing these differences in rat was aimed in this study.

DESIGN AND METHODS

To that end, F2 rats obtained from the crossbreeding between LOU/C and Fischer 344 rat strains to diet self-selection during 3 weeks were submitted. A genome scan was conducted with microsatellite markers covering evenly the whole genome. Genotypes and phenotypes were analyzed separately in male and female F2 rats by multiple interval mapping. Then, lists of candidate genes were treated by the Ingenuity Pathway software to propose gene pathways involved in our phenotypes.

RESULTS

Among numerous others, a QTL on chromosome 12 that influences body weight gain, and fat and carbohydrate choices in the LOU/C x Fischer 344 F2 rat population was found. This locus contains notably the acyl-co-A dehydrogenase gene.

CONCLUSION

A strong genetic determinism and complex pathways involving numerous candidate genes and processes, notably in accordance with the metabolic theory of feeding behavior control were found.