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Abstract: Familial LCAT deficiency (FLD) is a rare genetic disorder associated with corneal opacities, anaemia and proteinuria with renal failure. Here we report detailed analyses on plasma lipids, lipoproteins, and the molecular defect in two siblings from a Polish family presenting classical symptoms of FLD and their family members with newly discovered Val309Met mutation in exon 6 of LCAT gene. Both patients displayed low total (2.19 and 2.94mmol/l) and HDL-cholesterol concentrations (0.52 and 0.48mmol/l), low percentage of cholesteryl esters (CE) (11.1 and 12%), and decreased apo AI and apo AII serum levels. Low LDL-cholesterol, apo B and Lp(a) levels, and increased oleate/linoleate ratios in CE could be of importance in the development of atherosclerosis in these patients with low HDL-cholesterol. LCAT activity was 10% of normal, α-LCAT activity was 0, and LCAT concentration was undetectable by immunoassay. Plasma CETP activity was at lower limits of normal. PCR and sequence analysis of DNA from the proband and affected brother revealed a novel G→A mutation in exon 6 of LCAT gene, which resulted in an amino acid substitution of valine for methionine (Val309Met). The proband and affected brother were both homozygous carriers, while the mother, siblings and children of patients were heterozygous carriers of a newly discovered mutation. This is the first LCAT mutation described in the Slavic population. [Copyright &y& Elsevier]

Background: Glucometry is an essential part of diabetes treatment, but so far, no standard quality control procedure verifying blood glucose meter results is available. In this study, we evaluated the analytical performance of eight glucose meters: GX and Esprit™ (Bayer Diagn.), MediSense® Card Sensor, ExacTech (MediSense®) with strips Selfcare™ (Cambridge Diagn), One Touch® Basic, One Touch® II, One Touch® Profile (Lifescan) and Glucotrend® (Boehringer Mannheim/Roche). Methods: The evaluation included within-run imprecision, linearity, comparison with the laboratory method and calculation of differences between individual glucometers. Results: Within-run imprecision ranged from 1.5% to 4.5%, linearity assessed as the correlation between measured and calculated glucose concentrations yielded r2 values from 0.97 to 0.981. Analytical bias of glucose concentration values obtained by the glucometry amounted from 0.14% to 16.9% of values measured by the laboratory method. Bias higher than 5% was found for One Touch® Basic, II and Profile meters (however, glucose concentrations in plasma obtained by the laboratory method One Touch® meters showed analytical bias from 3.0% to 8.8%). The regression analysis yielded slope values from 0.77 to 1.09 and r2 values from 0.86 to 0.98. The best correlations with the laboratory method were found for One Touch® Basic, II Profile, Glucotrend® and Esprit™ meters. The calculated differences between the individual glucose meters can constitute 0.02–1.49 mmol/l (0.96–26.9%) at glucose concentration 5.55 mmol/l, and 0.16–4.16 mmol/l (0.96–24.96%) at glucose concentration 16.67 mmol/l. Error grid analyses have shown that Glucometers One Touch® Basic and One Touch® Profile yielded all results in zone A (acceptable). The remaining glucometers yielded 1–7% of results in zones B (insignificant errors), C or D (lack of detection and treatment). Conclusions: All studied glucometers had both small deviation from laboratory reference values (<10%) and high concurrence with results obtained by the laboratory method. [Copyright &y& Elsevier]

Abstract: Objective: Molecular background of diabetic retinopathy (DR) remains unknown. An interesting group of candidate genes encode proteins involved in insulin resistance. Aim: To search for association between the PPARγ, calpain 10, PTPN1 genes and DR in type 2 diabetes mellitus (T2DM). Methods: We examined 238 T2DM subjects without DR (NDR) and 121 with DR (mean diabetes duration: 9.1±6.8 and 15.1±7.7, respectively). The subjects were genotyped for four markers: Pro12Ala of PPARγ, SNP43 of calpain 10, rs3787345 and rs754118 of PTPN1. The distributions of the genotypes were compared using the χ2-test and Fisher exact test. Results: The alleles and genotypes were not associated with DR in non-stratified analysis. To investigate the impact of T2DM duration, we performed analysis that excluded short duration NDR subjects and long-duration DR subjects. It allowed obtaining groups with similar T2DM duration but different DR status (DR: 88 individuals, 11.4±5.3 years; NDR: 136 individuals, 13.2 years±6.2, respectively). This analysis suggested that the alanine variant of Pro12Ala might be associated with decreased risk of DR (p =0.026 for alleles, p =0.038 and p =0.014 for genotypes in additive and dominant models, respectively). In multivariable logistic regression that included non-genetic parameters, Pro12Ala was not an independent risk factor (p =0.28). Further analysis showed, however, that Pro12Ala remained significant when urea level was excluded from the model. Conclusion: The alanine variant of the Pro12Ala polymorphism of PPARγ might be associated with decreased risk of DR in T2DM. This effect may be indirect, at least in part, due to diabetic kidney disease. [Copyright &y& Elsevier]

Introduction: It has recently been shown that polymorphisms of some genes might influence the genetic susceptibility to complex, multifactorial forms of type 2 diabetes mellitus (T2DM). One of those genes is peroxisome proliferator activated receptor γ (PPARγ). The PPARγ gene product is a nuclear hormone receptor that regulates adipogenesis and is a target for thiazolidinediones, medications enhancing sensitivity to insulin. The Pro12Ala amino acid variant of the PPARγ2 isoform is associated with T2DM in several populations. Aims: (1) To determine the allele and genotype frequency of the Pro12Ala PPARγ2 amino acid variant in a Polish population; (2) To search for the association of the Pro12Ala polymorphism with T2DM in the examined population. Methods: We included 644 individuals in this study: 366 T2DM patients with age of diagnosis greater than 35 years and 278 non-diabetic control subjects. The fragment of the PPARγ2 gene which contains the examined amino acid variant was amplified by polymerase chain reaction (PCR). Alleles and genotypes were determined based on electrophoresis of the DNA digestion products by the specific restriction enzyme BshI. Differences in distribution between the groups were examined by χ2 test. Results: The frequency of Pro/Ala alleles was similar in T2DM patients and in the control subjects (83.5%/16.5% vs. 84.5%/15.5%, respectively, P=0.607). Similarly, there was no difference between the groups when we analysed the genotype distribution. Stratification analyses based on age of diagnosis, body mass index (BMI), and family history of T2DM were performed. The Pro/Ala and Ala/Ala genotypes tended to be more frequent in T2DM cases with age of diagnosis >50 years than in controls (36.2% vs. 27.3%, P=0.046). This difference was not significant after Sheffe correction for multiple comparisons. The other stratification analyses did not show any difference between the groups. Conclusion: The frequency of the Pro12Ala PPARγ2 polymorphism in the Polish population studied is similar to that in other Caucasian populations. In the case-control study, we were not able to confirm earlier reports that the Pro allele conferred an increased risk for development of T2DM. Moreover, the results of the stratified analysis suggest an opposite trend in late onset T2DM. [Copyright &y& Elsevier]

Polymorphisms of the genes involved in the metabolism of vitamin D may predispose to type 2 diabetes mellitus (T2DM). For example, there is evidence suggesting that vitamin D binding protein (DBP) amino acid variants at codons 416 (aspartic acid→glutamic acid) and 420 (threonine→lysine) may affect genetic susceptibility to T2DM. The aims of this study are: (1) to determine the allele, genotype, haplotype and haplotype combination frequencies of those DBP amino acid variants in a Polish population and (2) to examine their role in the genetic susceptibility to T2DM in a Polish population. Overall 393 individuals were included in this study: 231 T2DM patients and 162 controls. The sequence of DBP exon 11, which contains both examined variants, was amplified by polymerase chain reaction (PCR). Alleles and genotypes were determined based on electrophoresis of the DNA digestion products by specific restriction enzymes HaeIII and StyI. Since variants of DBP were in very strong linkage disequilibrium, haplotypes could be assigned to phase-unknown individuals. Differences in distributions between the groups were examined by χ2 test. At codon 416 the frequency of Asp/Glu alleles was 44.6/55.4% in T2DM patients and 40.7/59.3% in controls (χ2=2.1, d.f.=1, P=0.28). At codon 420 the frequency of Thr/Lys alleles were 69.4/30.6% and 71.6/28.4%, (χ2=0.41, d.f.=1, P=0.52), respectively. Distribution of genotypes, haplotypes and haplotype combinations were similar in both groups. In conclusion, the frequency of amino acid variants at codons 416 and 420 of vitamin D binding protein gene in a Polish population is similar to other Caucasian populations, but differs significantly from other races. No evidence was found for an association between DBP frequent polymorphisms and T2DM in this population. [Copyright &y& Elsevier]