Association of the human Y chromosome with cholesterol levels in the general population.

OBJECTIVE: Males are at higher risk of cardiovascular diseases than females. The aim of the study was to test whether the potential of the Y chromosome to affect cardiovascular risk could be attributed to its influence on lipids. METHODS AND RESULTS: 1288 Polish men (1157 subjects from young healthy cohort and 131 individuals from middle-aged hypertensive population) were phenotyped for determinants of cardiovascular risk including BMI, blood pressures, lipids, and testosterone. Each subject was genotyped for the HindIII(+/-) polymorphism within the nonrecombining region of the Y chromosome. Men with the HindIII(-) variant exhibited significantly higher total cholesterol (TC) and low-density lipoprotein cholesterol (LDL) levels than subjects with the HindIII(+) genotype in both populations. The differences between the genotypes were 0.15 mmol/L (P=0.0107) and 0.45 mmol/L (P=0.0377) in TC and 0.15 mmol/L (P=0.0059) and 0.41 mmol/L (P=0.0432) in LDL among young apparently healthy men and middle-aged hypertensive men, respectively. The HindIII(+) was associated with a significant increase in blood pressure of the middle-aged men. Testosterone serum concentrations correlated positively with HDL-cholesterol levels, and this association was independent of the Y chromosome. CONCLUSIONS: The results indicate that a locus/loci on the Y chromosome may influence LDL levels, independent of testosterone levels.

[Monogenic hypertension]. / Jednogenowe postacie nadcisnienia tetniczego.

The results of many studies performed on animals and humans strongly suggest that genetic factors lead to the development of hypertension (HT). Syndromes in which mutations in single genes are sufficient to result in large changes of blood pressure are rare. Nevertheless, it is anticipated that their understanding will lead to new insights into forms of hypertension occurring more often, including essential hypertension. At least 9 monogenic forms of HT including Liddle syndrome, type I familial hyperaldosteronism (GRA) and type II familial hyperladosteronism, Gordon syndrome, apparent mineralocorticoid excess syndrome (AME), hypertension associated with type E brachydactyly, glucocorticoid receptor mutations, type IV congenital adrenal hyperplasia (CAH) (11 beta-hydroxylase deficiency), and type V CAH (17 alpha-hydroxylase deficiency) have been described so far.

Epistatic interaction between beta2-adrenergic receptor and neuropeptide Y genes influences LDL-cholesterol in hypertension.

Beta2-adrenergic receptor gene and neuropeptide Y gene may potentially influence lipid metabolism and overall energy balance. Therefore, we examined associations of these genes with lipid fractions and obesity-related phenotypes in hypertensive subjects. A total of 638 white individuals from 212 Polish families with clustering of essential hypertension were phenotyped for cardiovascular risk determinants. Each subject was genotyped for functional polymorphisms of beta2-adrenergic receptor gene (Arg16Gly and Gln27Glu) and neuropeptide Y (Leu7Pro). Of 3 common haplotypes of beta2-adrenergic receptor gene, Arg16Gln27 was overtransmitted to offspring with elevated levels of total cholesterol (Z=2.2; P=0.026) and LDL-cholesterol (Z=3.2; P=0.002). Individually, Leu7Pro was not associated with any of the metabolic phenotypes in family-based tests or case-control analyses. However, in the presence of Arg allele of Arg16Gly and Gln allele of Gln27Glu, homozygosity for Leu variant of the Leu7Pro polymorphism was associated with 2.1-increased odds ratio (confidence interval, 1.10 to 3.81; P=0.024) of elevated LDL in hypertensive subjects, independent of age, gender, body mass index, adjusted blood pressures, antihypertensive therapy, and use of nonselective beta-blockers and diuretics. Consistently, there was a significant multilocus association among variants of Arg16Gly, Gln27Glu, and Leu7Pro in hypertensive probands with elevated LDL (cases; P=0.028) but not in hypertensive subjects with normal LDL (controls). This study revealed an association of LDL-cholesterol with beta2-adrenergic receptor gene haplotype and provided evidence for epistatic interaction between beta2-adrenergic receptor gene and neuropeptide Y gene in determination of LDL-cholesterol in patients with essential hypertension.

[Relationship between SA gene Pst1 polymorphism and predisposition to H-gestosis]. / Zwiazek pomiedzy polimorfizmem Pst1 genu SA a predyspozycja do H-gestozy.

Genetic factors have been reported to play an important role in the predisposition to development of pregnancy-induced hypertension (PIH). On the other hand, there is strong evidence that genetic factors play important role in the predisposition to essential hypertension. Recently, the plausible "candidate gene" for the development of hypertension is SA gene. The aim of our study was to assess the association of the SA gene with the susceptibility to PIH. For that purpose, the SA gene A1A2 polymorphism was studied in 124 women (median age 28 yrs) suffering from PIH in comparison with 148 healthy pregnant women (median age 28 yrs). Genotyping was performed using methods based on polymerase chain reaction. In this study we found statistically significant more frequent of genotype A1A1 occurrence in the patients with PIH when compared to healthy pregnant controls. The frequency of A1 allele was also significant higher in PIH in comparison with controls (chi 2 test.) Based upon the results of our study we can suspect that the SA gene Pst1 polymorphism is associated with the predisposition to PIH in caucasian women.

Angiotensin I-converting enzyme and chymase gene polymorphisms - relationship to left ventricular mass in type 2 diabetes patients.

BACKGROUND: Type 2 diabetic patients are at increased risk for cardiovascular morbidity and mortality. Increased left ventricular mass also predicts a higher incidence of cardiovascular events. Angiotensin II is a potent mediator of myocardial growth, and angiotensin II can be produced in the heart by angiotensin I-converting enzyme (ACE) and heart chymase (CMA). The aim of this study was to establish the role of ACE gene insertion/deletion (I/D) and CMA gene CMA/B polymorphisms in determining left ventricular mass in type 2 diabetic patients. MATERIAL/METHODS: Echocardiographic measurements, ACE gene I/D and CMA/B genotypes were determined in 154 type 2 diabetic patients. RESULTS: Mean LVMI was higher among DD homozygotes compared to heterozygotes and II homozygotes (128.9 g/m2 vs. 120.5 g/m2 and 120.4 g/m2, respectively), but the difference was not statistically significant (ANOVA P=0.12). A similar effect was observed for the CMA/B polymorphism, where mean LVMI were 126.6 g/m2, 122.1 g/m2 and 118.2 g/m2, for carriers of AA, AG and GG genotype, respectively (not statistically significant, P=0.33). ACE I/D and CMA/B polymorphism were also analyzed jointly, and carriers of both DD and AA genotypes were found to have significantly higher LVMI values (P=0.05) than non-carriers (133.0 g/m2 and 121.2 g/m2, for 21 DD and AA carriers vs. 133 non-carriers). In multivariate analysis, the presence of DD and AA genotypes was independently associated with LVMI (P=0.04). CONCLUSIONS: Our results may suggest the additive effect of ACE and CMA gene polymorphisms on the increase in left ventricular mass in NIDDM patients.

The Y chromosome effect on blood pressure in two European populations.

Higher blood pressure (BP) in males compared with females is well documented and is thought to be influenced in part by the Y chromosome. To examine whether there is an association between BP and a polymorphic HindIII biallelic marker in the nonrecombining region of the Y chromosome, we genotyped 155 males from a Polish study group and 762 males from a Scottish study group. We also tested for possible interaction between the Y chromosome and a mutation in the steroidogenic factor binding site of the aldosterone synthase gene by genotyping the same group from Scotland. There was no significant difference in age or body mass index between 2 Y chromosome genotypes in both study groups. Men with the HindIII(+) genotype had significantly higher systolic and diastolic pressures than those with the HindIII(-) genotype in both the Polish and Scottish studies. This difference between the genotypes was 5.27 mm Hg (P=0.0014) and 3.14 mm Hg (P=0.0005) for adjusted systolic BP and 2.6 mm Hg (P=0.0045) and 1.44 mm Hg (P=0.0084) for adjusted diastolic BP in the Polish and the Scottish studied, respectively. On binary logistic regression analysis, males with the HindIII(+)/TT SF1 genotype combination had an odds ratio for elevated BP of 3.92 (CI 1.21 to 12.68, P=0.023). Our results indicate that the Y chromosome harbors a locus or loci that contribute to BP variation in hypertensive and normotensive men. The polymorphism in the aldosterone synthase gene may interact with the Y chromosome to increase the odds of an individual's developing higher BP.

Essential hypertension and beta2-adrenergic receptor gene: linkage and association analysis.

A region on human chromosome 5 (5q31.1-qter) contains several genes that encode important blood pressure regulators and thus is a good candidate for analysis of linkage and association with hypertension. We recruited 638 individuals from 212 Polish pedigrees with clustering of essential hypertension. These subjects were genotyped for 11 microsatellite markers that span this region to test for linkage to essential hypertension and systolic and diastolic blood pressures. The segment of this region of approximately 7 cM delineated by D5S1480 and D5S500 markers was linked to blood pressures in multipoint analysis. In 2-point analysis, D5S1480--the marker in close proximity to beta2-adrenergic receptor gene--reached the maximal linkage to essential hypertension and adjusted systolic and diastolic blood pressures, implicating this gene as a positional candidate for further association studies. Arg16Gly, Gln27Glu, and Thr164Ile--3 functional single nucleotide polymorphisms within the beta2-adrenergic receptor gene--were tested for association with essential hypertension. None of these polymorphisms showed a significant association with essential hypertension, separately or in the haplotype analysis. This study provided evidence of linkage of 5q31.1-5qter region to essential hypertension in the European population. Moreover, it implicated the chromosomal segment in close proximity to D5S1480 and D5S500. The detailed analysis of 3 single nucleotide polymorphisms does not support the role of the beta2-adrenergic receptor gene as a major causative gene for the detected linkage.