Interaction between Cholesteryl Ester Transfer Protein and Hepatic Lipase Encoding Genes and the Risk of Type 2 Diabetes: Results from the Telde Study

BACKGROUND AND AIM: Diabetic dyslipidaemia is common in type 2 diabetes (T2D) and insulin resistance and often precedes the onset of T2D. The Taq1B polymorphism in CETP (B1 and B2 alleles) (rs708272) and the G-250A polymorphism in LIPC (rs2070895) are associated with changes in enzyme activity and lipid concentrations. Our aim was to assess the effects of both polymorphisms on the risk of T2D. METHODS AND RESULTS: In a case-control study from the population-based Telde cohort, both polymorphisms were analysed by PCR-based methods. Subjects were classified, according to an oral glucose tolerance test, into diabetic (N = 115) and pre-diabetic (N = 116); 226 subjects with normal glucose tolerance, matched for age and gender, were included as controls. Chi-square (comparison between groups) and logistic regression (identification of independent effects) were used for analysis. The B1B1 Taq1B CETP genotype frequency increased with worsening glucose metabolism (42.5%, 46.1% and 54.3% in control, IGR and diabetic group; p = 0.042). This polymorphism was independently associated with an increased risk of diabetes (OR: 1.828; IC 95%: 1.12-2.99; p = 0.016), even after adjusting by confounding variables, whereas the LIPC polymorphism was not. Regarding the interaction between both polymorphisms, in the B1B1 genotype carriers, the absence of the minor (A) allele of the LIPC polymorphism increased the risk of having diabetes. CONCLUSION: The presence of the B1B1 Taq1B CETP genotype contributes to the presence of diabetes, independently of age, sex, BMI and waist. However, among carriers of B1B1, the presence of GG genotype of the -250 LIPC polymorphism increases this risk further

Age, Origin and Functional Study of the Prevalent LDLR Mutation Causing Familial Hypercholesterolaemia in Gran Canaria

The p.(Tyr400_Phe402del) mutation in the LDL receptor (LDLR) gene is the most frequent cause of familial hypercholesterolaemia (FH) in Gran Canaria. The aim of this study was to determine the age and origin of this prevalent founder mutation and to explore its functional consequences. For this purpose, we obtained the haplotypic information of 14 microsatellite loci surrounding the mutation in one homozygous individual and 11 unrelated heterozygous family trios. Eight different mutation carrier haplotypes were identified, which were estimated to originate from a common ancestral haplotype 387 (110–1572) years ago. This estimation suggests that this mutation happened after the Spanish colonisation of the Canary Islands, which took place during the fifteenth century. Comprehensive functional studies of this mutation showed that the expressed LDL receptor was retained in the endoplasmic reticulum, preventing its migration to the cell surface, thus allowing us to classify this LDLR mutation as a class 2a, defective, pathogenic variant.This work was supported by grants from the Instituto de Salud Carlos III (ISCIII): PI20/00846, INT21/00032 (RMS), CM19/00116 (AMGL) with the participation of the European Union through European Regional Development Funds (“A way to make Europe”), the Fundación Canaria del Instituto de Investigaciones Sanitarias de Canarias (FCIISC): PIFIISC20/16 and the Fundación Mapfre Guanarteme (Beca Investigación 2020). NMS was supported by a María Zambrano Fellowship funded by the Spanish Ministry of Universities within the “Next Generation EU” scheme

Quality control of phenotypic forms data in the Type 1 Diabetes Genetics Consortium

Background When collecting phenotypic data in clinics across the globe, the Type 1 Diabetes Genetics Consortium (T1DGC) used several techniques that ensured consistency, completeness, and accuracy of the data

ViDa1: The Development and Validation of a New Questionnaire for Measuring Health-Related Quality of Life in Patients with Type 1 Diabetes

IGTPAltres ajuts: Funding was provided by the Canarian Agency for Research,Innovation and Information Society (ACIISI) (DA predoctoralfellowship TESIS20120050) and the V Guido Ruffino Grantfor Research in Therapeutic Education for Diabetes (SpanishDiabetes Society 2015)This study describes the development of a new questionnaire to measure health-related quality of life (HRQoL) in patients with type 1 diabetes (the ViDa1 questionnaire) and provides information on its psychometric properties. For its development, open interviews with patients took place and topics relevant to patients' HRQoL were identified and items were generated. Qualitative analysis of items, expert review, and refinement of the questionnaire followed. A pilot study (N = 150) was conducted to explore the underlying structure of the 40-item ViDa1 questionnaire. A Principal Component Analysis (PCA) was performed and six of the items that did not load on any of the factors were eliminated. The results supported a four-dimensional structure for ViDa1, the dimensions being Interference of diabetes in everyday life, Self-care, Well-being, and Worry about the disease. Subsequently, the PCA was repeated in a larger sample (N = 578) with the reduced 34-item version of the questionnaire, and a Confirmatory Factor Analysis (CFA) was performed (N = 428). Overall fit indices obtained presented adequate values which supported the four-factor model initially proposed [(2(df =554) = 2601.93) (p < 0.001); Root Mean Square Error of Approximation = 0.060 (CI = 0.056 −0.064)]. As regards reliability, the four dimensions of the ViDa1 demonstrated good internal consistency, with Cronbach's alphas ranging between 0.71 and 0.86. Evidence of convergent-discriminant validity in the form of high correlations with another specific HRQoL questionnaire for diabetes and low correlations with other constructs such as self-efficacy, anxiety, and depression were presented. The ViDa1 also discriminated between different aspects of clinical interest such as type of insulin treatment, presence of chronic complications, and glycemic control, temporal stability, and sensitivity to change after an intervention. In conclusion, the ViDa1 questionnaire presents adequate psychometric properties and may represent a good alternative for the evaluation of HRQoL in type 1 diabetes

Diabetes and Familial Hypercholesterolemia: Interplay between Lipid and Glucose Metabolism

Familial hypercholesterolemia (FH) is a genetic disease characterized by high low-density lipoprotein (LDL) cholesterol (LDL-c) concentrations that increase cardiovascular risk and cause premature death. The most frequent cause of the disease is a mutation in the LDL receptor (LDLR) gene. Diabetes is also associated with an increased risk of cardiovascular disease and mortality. People with FH seem to be protected from developing diabetes, whereas cholesterol-lowering treatments such as statins are associated with an increased risk of the disease. One of the hypotheses to explain this is based on the toxicity of LDL particles on insulin-secreting pancreatic β-cells, and their uptake by the latter, mediated by the LDLR. A healthy lifestyle and a relatively low body mass index in people with FH have also been proposed as explanations. Its association with superimposed diabetes modifies the phenotype of FH, both regarding the lipid profile and cardiovascular risk. However, findings regarding the association and interplay between these two diseases are conflicting. The present review summarizes the existing evidence and discusses knowledge gaps on the matter