Non-synonymous single-nucleotide polymorphisms associated with blood pressure and hypertension

In this study, we determined the association of 1180 non-synonymous single-nucleotide polymorphisms (SNPs) with systolic blood pressure (SBP) and hypertensive status. A total of 8842 subjects were taken from two community-based cohorts--Ansung (n=4183) and Ansan (n=4659), South Korea--which had been established for genome-wide association studies (GWAS). Five SNPs (rs16835244, rs2286672, rs6265, rs17237198 and rs7312017) were significantly associated (P-values: 0.003-0.0001, not corrected for genome-wide significance) with SBP in both cohorts. Of these SNPs, rs16835244 and rs2286672 correlated with risk for hypertension. The rs16835244 SNP replaces Ala288 in arginine decarboxylase (ADC) with serine, and rs2286672 replaces Arg172 in phospholipase D2 (PLD2) with cysteine. A comparison of peptide sequences between vertebrate homologues revealed that the SNPs identified occur at conserved amino-acid residues. In silico analysis of the protein structure showed that the substitution of a polar residue, serine, for a non-polar alanine at amino-acid residue 288 affects a conformational change in ADC, and that Arg172 in PLD2 resides in the PX domain, which is important for membrane trafficking. These results provide insights into the function of these non-synonymous SNPs in the development of hypertension. The study investigating non-synonymous SNPs from GWAS not only by statistical association analysis but also by biological relevance through the protein structure might be a good approach for identifying genetic risk factors for hypertension, in addition to discovering causative variations.

Impact of medical Qigong on quality of life, fatigue, mood and inflammation in cancer patients: a randomized controlled trial

Background: Substantial numbers of cancer patients use complementary medicine therapies, even without a supportive evidence base. This study aimed to evaluate in a randomized controlled trial, the use of Medical Qigong (MQ) compared with usual care to improve the quality of life (QOL) of cancer patients.

Patients and methods: One hundred and sixty-two patients with a range of cancers were recruited. QOL and fatigue were measured by Functional Assessment of Cancer Therapy—General and Functional Assessment of Cancer Therapy—Fatigue, respectively, and mood status by Profile of Mood State. The inflammatory marker serum C-reactive protein (CRP) was monitored serially.

Results: Regression analysis indicated that the MQ group significantly improved overall QOL (t₁₄₄ = −5.761, P < 0.001), fatigue (t₁₅₃ = −5.621, P < 0.001), mood disturbance (t₁₂₂ =2.346, P = 0.021) and inflammation (CRP) (t₉₉ = 2.042, P < 0.044) compared with usual care after controlling for baseline variables.

Conclusions: This study indicates that MQ can improve cancer patients’ overall QOL and mood status and reduce specific side-effects of treatment. It may also produce physical benefits in the long term through reduced inflammation.

Randomized clinical trial of medical qigong on quality of life, fatigue, side effects, mood, status, and inflammation of cancer patients

9617

Background: The quality of life (QOL) of cancer patients is often diminished due to the side effects of treatment and symptoms of the disease itself. This study examines the impact of Medical Qigong (MQ), including gentle exercise and relaxation through meditation and breathing exercise based on the Chinese Medicine theory of energy channels, on quality of life (QOL), fatigue, side effects, mood status and inflammation. Methods: One hundred sixty two patients diagnosed with a range of cancers recruited from three university teaching hospitals were randomly assigned to two groups: a control group (n=83) that received usual health care and an intervention group (n=79) who participated in a MQ program for 10 weeks in addition to receiving usual health care at the hospital. Quality of life and symptoms were measured by the FACT-G, cancer related fatigue by FACT-F and mood status by POMS. The inflammatory marker serum C-reactive protein (CRP) was also monitored serially. Results: Regression analysis indicated that the MQ intervention group significantly improved on measures of overall QOL (t144= -5.761, p<0.001), fatigue (t153= -5.621, p<0.001), mood disturbance (t122=2.346, p=0.021) and inflammation (CRP) (t99=2.042, p<0.044) compared to the usual care control group after controlling for baseline variables. Analysis of the FACT-G subscales revealed that the MQ intervention group also significantly improved in satisfaction with sex life (t92=-3.783, p<0.001) and reduced side effects of nausea (t152=-2.071, p=0.040) and sleep disturbance (t150=-2.603, p=0.010) compared to the usual care control group. Pain was improved in both intervention and control groups. Conclusions: This study suggests that MQ with usual health care can improve overall QOL, fatigue, positive mood status and reduce the side effects of nausea, sleep disturbance and inflammation of cancer patients. This study supports the use of MQ as an intervention for cancer care.

No significant financial relationships to disclose.

Genetic association study of polymorphisms in the catalase gene with the risk of osteonecrosis of the femoral head in the Korean population

OBJECTIVE

Osteonecrosis (ON) of the femoral head frequently leads to progressive collapse of the femoral head followed by degenerative arthritis of the hip joint. Oxidative stress, which has been implicated in many pathological conditions, including vascular injury, recently has been suggested to play a part in the development of ON. Catalase (CAT) is a major antioxidant enzyme and a number of polymorphisms in the CAT have been described as being associated with several diseases, such as hypertension, diabetes mellitus, Alzheimer's disease, and vitiligo. The aim of this study was to evaluate the association of CAT gene polymorphisms with ON of the femoral head (ONFH) in a case-control study.

METHODS

Eight polymorphic sites of CAT were selected from public databases, and genotyped in 443 ONFH patients and 273 control subjects using the Affymetrix Targeted Genotyping (TG) 3K chip array. The association analysis of genotyped single nucleotide polymorphisms (SNPs) and haplotypes was performed with ONFH.

RESULTS

The -89A>T, -20T>C, +3033C>T, +14539A>T, +22348C>T, and +24413T>C polymorphisms of the CAT gene were significantly associated with the risk of ONFH in all alternative analysis models (P range; 0.0001-0.035, odds ratio [OR]: 0.52-3.47). Particularly, the minor allele of -89A>T, -20T>C and +3033C>T had a protective effect on ONFH with significance (P range: 0.0014-0.035, OR: 0.52-0.73). Further analysis based on pathological etiology showed that the genotypes of -89A>T, -20T>C, +3033C>T, +14539A>T, and +22348C>T, and +24413T>C were also associated with the risk of ONFH in each subgroup with significant P values.

CONCLUSIONS

These findings indicate that the polymorphisms of CAT are associated with the ONFH, and suggest that oxidative stress may play an important role in the pathogenesis of ONFH.

Promoter polymorphisms of the vascular endothelial growth factor gene is associated with an osteonecrosis of the femoral head in the Korean population

OBJECTIVE

Disruption of the vascular supply to the bone and subsequent hypoxia has been implicated in the pathogenesis of osteonecrosis of the femoral head (ONFH). Vascular endothelial growth factor (VEGF), a major inducer of angiogenesis, has been correlated with several pathological conditions, from inflammation to ischemic processes. A number of polymorphisms in the VEGF gene have been described as being associated with several diseases, such as diabetic retinopathy, prostate cancer and breast cancer. The aim of this study was to evaluate the association of VEGF gene polymorphisms with ONFH in a case--control study.

METHODS

Three polymorphisms (-2578C>A, -634G>C and +936C>T) in VEGF were genotyped in 317 ONFH patients and 497 control subjects, using the TaqMan 5' allelic discrimination assay. We performed the association analysis of genotyped single nucleotide polymorphisms (SNPs) and haplotypes with ONFH.

RESULTS

The -634G>C genotype was significantly associated with an increased risk for ONFH in dominant model with odds ratio (OR) of 1.47, 95% confidence intervals (CIs) 1.08-2.01 with P value 0.015. Further analysis stratified by sex showed that the -634G>C genotype was also significantly associated with a high risk for male patients considering the dominant model with OR of 1.60, 95% CI 1.13-2.26 with P value 0.008. Haplotype association analysis did not provide a further delineation of the risk allele.

CONCLUSION

Our study is, to our knowledge, the first report that shows the -634G>C polymorphism in the VEGF promoter was associated with an increased susceptibility of ONFH in the Korean population.

Allelic frequencies and heterozygosities of microsatellite markers covering the whole genome in the Korean

Microsatellite markers are an essential tool for genetic linkage analysis because of their high polymorphism content. Four hundred commercially available markers covering the entire genome were genotyped from 578 sib individuals from 249 Korean families. Allelic frequencies and heterozygosities were determined for each marker loci and compared between Korean, Taiwanese, Japanese and Caucasian populations. In the three Asian populations, 10-13% of the markers had less than 0.6 heterozygosity, whereas in the Caucasian population, only 0.5% of the markers had less than 0.6 heterozygosity. Mean identical by descent (IBD) values were calculated for 578 sib individuals. Analysis of IBD values greater than 0.5 suggested that markers with low heterozygosity can also provide positive linkages, at least for the IBD sharing method of model-free linkage analysis. The data presented in this study will be a useful reference for genome-wide screens of Koreans and comparative studies with other ethnic populations.

A promoter nucleotide variant of the dendritic cell-specific DCNP1 associates with serum IgE levels specific for dust mite allergens among the Korean asthmatics

Dendritic cells (DCs), the most abundant antigen-presenting cells in the lung, have been drawing attention for their roles in specific allergic responses to aeroallergens with support of Th lymphocytes, and in persistent inflammatory changes in allergic asthma. To identify genetic factors that may be involved in the asthma susceptibility and development of the disease phenotypes, we examined association of DC-specific DCNP1 polymorphisms with the disease risk. The case-control study revealed association of the nucleotide variants with serum immunoglobulin E (IgE) levels specific for Dermatophagoides farinae (Der f 1) and Dermatophagoides pteronyssinus (Der p 1), major aeroallergens of dust mites, among subjects with asthma. In particular, the T-allele-carrying genotype frequencies for one of the variants (c.-1289C>T) located in the promoter region were found increased in the asthmatic group with low levels of the mite-specific IgE (odds ratio (OR)=0.63 (0.48-0.83) for Der p 1). Results from functional analyses indicated that the promoter variant would affect the gene expression by modulating DNA-protein interaction. We propose that the genetic polymorphism of DCNP1 may influence production of specific IgE by altering DC functions in the mite allergen presenting and/or processing. The functional relevance of the genetic variation would provide an important insight into the genetic basis of allergic response to the mite antigens.

Putative association of peroxisome proliferator-activated receptor gamma co-activator 1beta (PPARGC1B) polymorphism with Type 2 diabetes mellitus

AIMS

Peroxisome proliferator-activated receptor gamma co-activator 1beta (PPARGC1B) may play an important role in obesity and Type 2 diabetes mellitus (T2DM). In an effort to identify genetic polymorphisms in potential candidate genes for T2DM, genetic associations of PPARGC1B were examined in a Korean T2DM study.

METHODS

We have sequenced the PPARGC1B, and examined its association with T2DM and diabetic phenotypes in a Korean T2DM study (775 T2DM patients and 316 control subjects) using the TaqMan method. Logistic and multiple regression models were employed to analyse the genetic contributions of polymorphisms. Nineteen polymorphisms were identified in PPARGC1B.

RESULTS

By logistic regression analysis controlling for age and sex as covariates, one non-synonymous single-nucleotide polymorphism (SNP; +102605C>A; Arg292Ser) in exon 5 showed marginal significant associations with the risk of T2DM. The allele frequency of the minor allele ['A (= Ser)' allele of +102605C>A] was lower among T2DM patients (frequency = 0.101) than among control subjects (frequency = 0.135) [P = 0.03, OR = 0.71 (95% CI: 0.51-0.94)]. Furthermore, serum triglyceride level was also associated with this non-synonymous SNP (+102605C>A; Arg292Ser) in exon 5 among controls (P = 0.03 in the dominant analysing model). Serum triglyceride levels [1.46 +/- 0.70 (log-transformed value; 0.12 +/- 0.18)] were lower in individuals who carry one or two copies of minor alleles than among others [1.60 +/- 0.85 (log-transformed value; 0.16 +/- 0.21)].

CONCLUSION

The present study provides, for the first time, information about genetic polymorphisms in PPARGC1B and putative associations of one non-synonymous SNP with the risk of T2DM and serum triglyceride (TG) levels in the Korean population, although this result was not significant after correction for multiple testing.

Association of PLXNA2 polymorphisms with vertebral fracture risk and bone mineral density in postmenopausal Korean population

INTRODUCTION

Plexin A2 (PLXNA2) is a receptor that recognizes secreted or membrane-bound semaphorin 3A, which is implicated in neural regulation of bone metabolism.

MATERIALS AND METHODS

In the present study, we identified 48 genetic polymorphisms in PLXNA2 by resequencing, and 10 single nucleotide polymorphisms (SNPs) were selected for further investigation into their potential involvement in osteoporosis in a postmenopausal population (n=560).

RESULTS

Two SNPs, +14G>A (Gln5Arg) and +183429C>T (Tyr1621Tyr), and Block1-ht2 were associated with risk of vertebral fracture (p=0.01-0.05), and three SNPs, +799G>A (Ala267Thr), +135391G>A, and +190531G>C, were associated with bone mineral density at various femur sites (p=0.003-0.03). Particularly, the minor allele of +14G>A was associated with a protective effect on vertebral fracture and higher lumbar bone mineral density, suggesting that +14G>A may be a useful marker for osteoporosis and its related fracture.

CONCLUSION

These results provide, for the first time, evidence supporting the association of PLXNA2 with osteoporosis in postmenopausal women.

Common promoter polymorphism in monocyte differentiation antigen CD14 is associated with serum triglyceride levels and body mass index in non-diabetic individuals

AIMS

Growing evidence supports the hypothesis that chronic low-grade inflammation related to innate immunity may play an important role in the pathophysiology of Type 2 diabetes mellitus (T2DM). The monocyte differentiation antigen CD14 gene (CD14) acts as the receptor for lipopolysaccharide (LPS) and augments monocyte/macrophage inflammatory responses.

METHODS

We have sequenced the gene, including all exons, exon/intron boundaries, and the -1.5 kb of the 5' flanking region. Two common loci (minor allele frequency > 0.05) were genotyped in 775 T2DM patients and 316 control subjects recruited in the Korean T2DM Study.

RESULTS

Eight polymorphisms, including four non-synonymous forms, were identified in CD14. No polymorphisms were found in association with T2DM. However, one common promoter SNP (-260T>C) was significantly associated with both the serum triglyceride level (TG) and body mass index (BMI) in non-diabetic control subjects. Individuals who carried the minor allele (C) had higher TG levels (1.65 +/- 0.81 vs. 1.46 +/- 0.80 mmol/l; P = 0.0007) and BMI (23.96 +/- 3.00 vs. 23.28 +/- 3.22 kg/m(2); P = 0.04) as compared with subjects carrying T/T genotypes.

CONCLUSION

Our data suggest that lipid metabolism and obesity, important pathophysiological elements of T2DM and the metabolic syndrome, are regulated by complex mechanisms that include the CD14 gene polymorphism-mediated genetic propensity to non-specific inflammatory responses.

Identification of four novel HLA-DOA alleles, DOA*010106, DOA*0102, DOA*0103, and DOA*0104N, by sequence-based typing*

DOA sequences are currently known to have identical protein sequences. However, in this study, we report four novel allele types of human leucocyte antigen-DOA, including one synonymous and three non- synonymous amino acid changes from the Korean population. DOA*010106 has identical protein sequence with previously known DOA*010103 except one nucleotide difference at codon 45 (TCG-->TCA). In contrast, DOA*0102 and DOA*0103 have a sequence change at codon 99 (CTG-->GTG) and codon 105 (CGC-->TGC), causing non-synonymous amino acid changes, Leu99Val and Arg105Cys, respectively. In addition, DOA*0104N has a sequence deletion at codon 36 (CCC-->CC-), resulting in a frame shift leading to a stop codon at codon 62.

Identification of a novel HLA-DOB-allele, DOB*010103, by sequence-based typing in the Korean population

A new DOB allele, DOB*010103, was identified in the Korean population during sequence-based HLA-DOB typing. DOB*010103 differed from DOB*01010101 only at codon 6 (GAT-->GAC), corresponding to synonymous amino acid change (Asp-->Asp).

Identification of a novel HLA-DQB1 allele, DQB1*0314, by sequence-based typing in the Korean population

The polymorphism of HLA class II genes is largely confined to the exon 2 region. Sequence analysis of exon 2 of the DQB1 gene revealed the novel polymorphism in the Korean population. The new DQB1 allele, DQB1*0314, was differed from DQB1*0304 only at codon 46 (GAG-->GGG), corresponding to non-synonymous amino acid change (Glu-->Gly).

Identification of a novel HLA-DMB allele (DMB*0107) in the Korean population

A novel allele for human leukocyte antigen-DMB was identified in the Korean population. DMB*0107 was identical to DMB*0101 at exon 2, apart from three mismatches at nucleotide positions 82 (A-->G), 146 (A-->T) and 212 (G-->A). These mutations resulted in codon changes at positions 10 (Thr-->Ala), 31 (Asp-->Val) and 53 (Ser-->Asn).

Potential predictors of asymptomatic ischemic heart disease in patients with vasculogenic erectile dysfunction

OBJECTIVES

To prospectively define the potential predictors of asymptomatic ischemic heart disease in patients with vasculogenic erectile dysfunction using a simple and practical method. Most patients with vasculogenic erectile dysfunction are known to have at least one significant cardiovascular risk factor.

METHODS

After baseline evaluations, patients with erectile dysfunction of presumed vascular origin, who were older than 45 years and with no history of ischemic heart disease, were enrolled in the study. According to the results of repeated pharmacologic erection tests, we divided patients into responders and nonresponders. The cardiologic evaluations consisted of a comprehensive history taking, the assessment of cardiovascular risk factors, a physical examination, and an exercise treadmill test.

RESULTS

A total of 97 patients completed the study. Fifteen (32.6%) of 46 responders and 25 (49.0%) of 51 nonresponders, respectively, had two or more cardiovascular risk factors (P = 0.101). Ischemic ST-segment changes on the exercise treadmill test were only observed in 8 nonresponders (15.7%) (P = 0.006). All these patients were older than 55 years, and seven had two or more cardiovascular risk factors, including hypertension.

CONCLUSIONS

On the basis of these preliminary data, we suggest that cardiovascular evaluations may prove beneficial before prescribing sildenafil to patients with vasculogenic erectile dysfunction who are nonresponders to the pharmacologic erection test, are older than 55 years, and have two or more risk factors, including hypertension.