Chinese Mongolian Population Research Articles

Analysis of Dietary Supplement Use and Influencing Factors in the Mongolian Population.

Objective Dietary supplements (DS) may improve micronutrient deficiencies, but the unique eating habits and cultural customs of the Chinese Mongolian population affect their choice of DS. Therefore, this study adopted a cross-sectional method to explore the current status of DS use and to assess the influencing factors in the Mongolian population in Inner Mongolia, China. Methods We used a multistage random cluster sampling method to select 1,434 Mongolian people aged ≥ 18 years in Hohhot and Xilinhot, Inner Mongolia. Data regarding general patient characteristics and DS use through questionnaire surveys were obtained, and the blood plasma was collected for biochemical index detection. The binary logistic regression and decision tree algorithm were used to predict the factors influencing DS use among the Mongolian population. Results Among 1,434 participants that completed the baseline survey, the usage rate of DS was 18.83%, and more women than men used DS (P = 0.017). Higher use of DS was reported among individuals aged ≤ 34 years, but this difference is not statistically significant (P = 0.052). Usage rate was higher among those living in urban areas (P < 0.001), those with higher education (P < 0.001), those engaged in mental work (P < 0.001), and nonsmokers (P = 0.019). The biochemical test results showed that the proportion of people with abnormal total cholesterol levels using DS was lower (P = 0.003), but that of those with abnormal triglyceride levels using DS was higher (P = 0.001), compared with the proportion of those with normal levels in each case. The most commonly used supplement was calcium (58.15%). Education level was the main factor affecting DS intake. The results of the binary logistic regression model and decision tree model both showed that region, educational level, and abnormal triglyceride levels were significant factors influencing DS intake among Mongolians. Conclusion Findings from this study indicate that DS intake is uncommon in the Mongolian population. In addition, sex, region, education level, and triglyceride levels may influence DS use.

Association of VEGFA polymorphisms with chronic obstructive pulmonary disease in Chinese Han and Mongolian populations.

What is the central question of this study? Vascular endothelial growth factor A (VEGFA) is an important growth factor involved in changes in the bronchial microvascular and airway inflammation in chronic obstructive pulmonary disease (COPD) progression. What is the association of single nucleotide polymorphisms (SNPs) in VEGFA with the risk of COPD in the Chinese Han and Mongolian populations? What is the main finding and its importance? The effect of five SNPs in the VEGFA gene was analysed and compared between the Chinese Han and Mongolian populations. A contribution of risk alleles rs833068, rs833070 and rs3024997 to COPD was detected in the Chinese Mongolian population only. The study provided data from different populations to validate the role of VEGFA polymorphisms in COPD and provided reliable SNPs to predict the risk of COPD. We attempted to define the associations between single nucleotide polymorphisms (SNPs) in the vascular endothelial growth factor A (VEGFA) gene and chronic obstructive pulmonary disease (COPD) in Chinese Han and Mongolian cohorts. Five SNPs were genotyped in cohorts of 684 COPD patients (350 Mongolian and 334 Han) and 784 healthy controls (350 Mongolian and 434 Han) using SNPscan multiplexPCR. SNP frequencies, genetic models and haplotypes were analysed using the chi-square test. The associations of SNPs with COPD and linkage disequilibrium were analysed using logistic regression and HaploView, respectively. We found that only rs833068G>A, rs833070T>C and rs3024997G>A were significantly associated with the risk of COPD in the Mongolian population (rs833068: P<0.001, rs833070: P<0.001, rs3024997: P=0.002). In the analysis of genotype distributions, the A/A and G/A genotypes in rs833068 (A/A: odds ratio (OR) = 0.313, P<0.001; G/A: OR=0.724, P<0.001) and rs3024997 (A/A: OR=0.513, P=0.008; G/A: OR=0.671, P=0.008) and the C/C and T/C genotypes in rs833070 (C/C: OR=0.435, P=0.007; T/C: OR=0.593, P=0.007) were associated with protection against COPD in the Mongolian population. The haplotype frequencies of GCCAT and GTCGC were significantly different between the patients and controls (GCCAT: P=0.001; GTCGC: P<0.001) in the Mongolian population. Our findings indicate that five SNPs in the VEGFA gene play divergent roles in the Han and Mongolian populations. rs833068A, rs833070C and rs3024997A were observed to be associated with the risk of COPD in the Mongolian population.

Multiple genetic analyses to investigate the polymorphisms of Chinese Mongolian population with an efficient short tandem repeat panel

AimTo determine allele frequencies and forensic statistics of 22 autosomal short tandem repeat loci in Chinese Mongolian population.MethodsBlood specimens were collected from 134 unrelated healthy Mongolian individuals, and 22 short tandem repeat loci were co-amplified and genotyped. Allele frequencies and forensic parameters were calculated, and population genetic differences were analyzed among Mongolian population and other eight Chinese populations: Northern Han, Guangdong Han, Chengdu Han, Xinjiang Hui, Xinjiang Uygur, Hainan Li, Qinghai Tibetan, and Hainan Han.ResultsAll the loci were in the Hardy-Weinberg equilibrium, and after Bonferroni correction there was no linkage disequilibrium between them. The allele frequencies of these 22 loci were between 0.0037 and 0.3657. This panel had high discriminating power and genetic polymorphism in the Mongolian population, with combined power of discrimination of 0.999999999999999999999999998399 and combined probability of exclusion of 0.9999999999566925. Structure analysis showed no evidence that these nine Chinese populations had different component distribution. However, genetic distance analysis showed significant differences among them (P < 0.05).ConclusionThe combined application of these 22 loci could be useful for forensic purposes in the Mongolian population. Mongolian population had smaller genetic distances from the populations in northern China (Northern Han, Xinjiang Uygur, and Xinjiang Hui) than from the populations in Hainan province (Hainan Han and Hainan Li populations).

Association of the CETP gene TaqIB and D442G polymorphisms with essential hypertension in the Chinese Mongolian population.

This study aimed to explore the associations of the cholesteryl ester transfer protein (CETP) gene TaqIB and D442G polymorphisms with essential hypertension (EH). In this case-control study, 883 hypertensive patients and 1044 normal controls were randomly selected from the Mongolian population of China. Polymerase chain reaction (PCR) and direct sequencing of PCR products were used to identify the genotypes. Haplotype analysis was performed by estimating the haplotype frequencies using the online SHEsis package. The distribution frequency of the B2-G haplotype was significantly lower in the EH group than in the control group (0.7% vs. 1.9%, P = 0.001, OR = 0.359 [0.188-0.689]). Subjects with the B2B2 genotype showed significantly lower levels of total cholesterol (TC) (P < 0.05). When subgrouped by sex, male subjects with the B2B2 genotype showed significantly increased high-density lipoprotein cholesterol and decreased TC levels (P < 0.05), and those with the B2 allele showed significantly lower triglyceride levels as compared to the subjects with the B1B1 homozygote (P < 0.05). TaqIB and D442G polymorphisms of the CETP gene did not independently affect the risk of developing EH in the Chinese Mongolian population, while the B2-G haplotype obviously decreased the susceptibility to EH. The B2 allele could alter the blood lipid level and reduce the risk of developing cardiovascular diseases.

Genetic polymorphisms and related risk factors of ischemic stroke in a Mongolian population in China

Ischemic stroke is caused by an interruption in the flow of blood to the brain and a risk factor for death and disability. Recent genome-wide association studies have identified more than 40 common sequence variants associated with ischemic stroke. However, the results are not always the same in populations with different genetic backgrounds. In the present study, we evaluated a hypothesis that a North Asian population living in a geographic area with unusually harsh environmental conditions would develop unique genetic risks. We investigated the candidate genes for ischemic stroke and risk factors in a Chinese Mongolian population which has not been explored previously. A total of 167 stroke cases and 176 controls were included in the study. Genotyping was performed by amplicon sequencing. The association was detected with single nucleotide polymorphisms (SNPs) located within genes NINJ2 (rs12425791) and ALDH2 (rs2238151) as well as intergenic rs9536591 were significantly associated with ischemic stroke, of which SNP rs12425791 of the NINJ2 gene was the strongest association. ALDH2 gene encodes mitochondrial aldehyde dehydrogenase, involved in the oxidative pathway of alcohol metabolism. Sex, age, body mass index and high blood pressure might be the risk factors. The current work also demonstrated genetic heterogeneity exists between Chinese and other populations. Our study provided the new insights into the genetic basis and environmental factors of ischemic stroke in Mongolian population.

Association of single nucleotide polymorphisms in the IL2RA-RBM17 region with vitiligo in the Chinese Mongolian population

Objective To investigate the association between single nucleotide polymorphisms(SNPs)in the IL2RA-RBM17 region and vitiligo in the Chinese Mongolian population. Methods Five milliliters of venous blood samples were collected from 425 patients with vitiligo(patient group)and 503 healthy human controls(control group)of Mongolian nationality after informed consent, and genomic DNA was extracted with the AxyPrep DNA extraction kit(AP-MX-BL-GDNA-25). Nine SNPs were selected across the IL2RA-RBM17 region, including rs706779, rs3134883, rs7090530, rs12251307, rs4750005, rs3920615, rs4747887, rs4750012 and rs7099083. Ligase detection reaction(LDR)was performed for SNP genotyping. With the PLINK 1.07 and SPSS 11.0 packages, statistical analysis was carried out by the chi-square test for comparisons of allele and genotype frequencies between the patient group and control group. Linkage disequilibrium analysis was performed for 5 SNPs by calculating the r2 and D' values. Haplotype analysis of 5 related SNPs was conducted to investigate differences in haplotype frequencies between the patient group and control group. Results There were significant differences in allele frequencies of 5 SNPs, including rs4750005, rs3920615, rs4747887, rs4750012 and rs7099083, between the patient group and control group(all P < 0.05). Under a dominant mode of inheritance, a significant decrease was observed in the frequencies of GG/GC genotypes of rs3920615, CT/CC genotypes of rs4747887, CT/CC genotypes of rs4750005, TC/TT genotypes of rs4750012 and AG/AA genotypes of rs7099083 in the patient group compared with the control group(all P < 0.005 6). Moderate to strong linkage disequilibrium was observed between the 5 SNPs(D' = 0.424-1, r2 = 0.137-0.985). Haplotype analysis showed that the frequency of a haplotype(H2: CGCTA)was significantly lower in the patient group than in the control group, and the difference reached statistical significance after Bonferroni adjustment(P= 0.001 6, OR = 0.674). Conclusion SNPs in the IL2RA-RBM17 region are associated with vitiligo in the Chinese Mongolian population. Key words: Vitiligo; Polymorphism, single nucleotide; Mongolia; Genetic association studies; Genes, IL2RA-RBM17; China

Characterization of a novel MICA allele, MICA*012:05, by cloning and sequencing.

A new MICA allelic variant, MICA*012:05, has been identified in a Chinese Mongolian population. Following polymerase chain reaction-sequence-based typing (PCR-SBT), this new allele was further confirmed by cloning and sequencing. MICA*012:05 was linked to an HLA-A*24-C*01-B*55:02-DRB1*09 haplotype. MICA*012:05 differs from MICA*012:01 by a single synonymous C to T substitution at nucleotide position 269 in exon 3.

MICA, MICB Polymorphisms and Linkage Disequilibrium with HLA-B in a Chinese Mongolian Population.

In this study, polymorphisms of major histocompatibility complex class I chain-related genes A and B (MICA and MICB) and human leucocyte antigen (HLA)-B gene were investigated for 158 unrelated Chinese Mongolian subjects recruited from central Inner Mongolia Autonomous Region, northern China, by polymerase chain reaction-sequence-based typing (PCR-SBT) and cloning. Collectively, 79 alleles, including 20 MICA, 12 MICB and 47 HLA-B alleles, were identified. MICA*008:01 (21.2%), MICB*005:02 (48.1%) and HLA-B*51:01 (7.91%) were the most common alleles. Significant global linkage disequilibrium (LD) was detected between HLA-B and MICA, HLA-B and MICB, and MICA and MICB loci (all P<0.000001). The most frequent haplotypes were HLA-B*51:01-MICA*009:01 (7.28%), HLA-B*58:01-MICB*008 (6.96%), MICA*010-MICB*005:02 (13.92%) and HLA-B*58:01-MICA*002:01-MICB*008 (6.96%). HLA-B-MICA haplotypes such as HLA-B*50:01-MICA*009:02 were associated with single MICB allele. Some HLA-B-MICA haplotypes were associated with multiple MICB alleles, including HLA-B*51:01-MICA*009:01. One novel MICB allele, MICB*031, was identified, which has possibly arisen from MICB*002:01 through single mutation event. We also confirmed the existence of a recently recognized MICA allele, MICA*073, whose ethnic origin has not been previously described. Genotype distributions at MICA, MICB and HLA-B were consistent with a neutrality model. Our results provide new insight into MIC genetic polymorphisms in Chinese ethnic groups. Findings shown here are important from an anthropologic perspective and will inform future studies of the potential role of MIC genes in allogeneic organ transplantation and HLA-linked disease association in populations of related ancestry.

Association between RNF41 gene c.-206 T > A genetic polymorphism and risk of congenital heart diseases in the Chinese Mongolian population.

This study aimed to explore the association between ring finger protein 41 (RNF41) c.-206 T > A variant and susceptibility to congenital heart disease (CHD) in the Chinese Mongolian population. The association between RNF41 gene c.-206 T > A polymorphism and CHD was examined in two independent case-control studies consisting of 219 CHD patients and 208 healthy controls. Genotype was determined by direct sequencing of PCR products. We found that the genotype frequencies of RNF41 c.-206 T > A differ significantly between the two groups (P < 0.05). The TT and TA genotypes in the CHD group were 80.67 and 19.33%, respectively. On the other hand, the frequencies of TT and TA in the control group were 94.44 and 5.56%, respectively. Furthermore, the allelic frequencies of CHD patients (T, 90.34%; A, 9.66%) were significantly different as compared with those of non-CHD controls (T, 97.22%; A, 2.78%; χ2 = 4.031, P = 0.041). Our study demonstrates that the RNF41 c.-206 T > A polymorphism may be a risk factor for congenital heart disease in the Chinese Mongolian population.

The distribution of genetic diversity of KIR genes in the Chinese Mongolian population

Killer cell immunoglobulin-like receptors (KIRs) are expressed on natural killer cells and as such regulate their response against infection and malignancy. KIR genes are variable in gene content and type, which results in different KIR haplotypes, and can be used to discriminate individuals and populations from different regions or ethnic groups. In the present study, we represent the first report on the KIR gene frequency and content diversities of 14 KIR genes (KIR2DL1, 2DL2, 2DL3, 2DL4, 2DL5, 2DS1, 2DS2, 2DS3, 2DS4, 2DS5, 3DL1, 3DL2, 3DL3, 3DS1) and 2 pseudogenes (KIR3DP1 and 2DP1) in the Chinese Mongolian population. The 16 detected KIR genes were all observed. All the individuals were typed positive for the four framework genes KIR3DL3, 3DL2, 2DL4 and the pseudogene KIR3DP1, as well as for the pseudogene KIR2DP1. The observed carrier gene frequencies (OF) of the other KIR genes ranged from 16% at the KIR2DL2 locus to 93% at the KIR3DL1 locus. Over all, 48 different gene profiles were found in the study population and the most commonly observed KIR gene profile with a frequency of 14% consisted of KIR2DL4, 3DL2, 3DL3, 2DP1, 3DP1, 2DL1, 2DL3 and 3DL1 which belongs to the AA genotype. Principal component analysis (PCA) and the dendrogram illustrated the genetic distances between our study population and previously published populations from other ethnic groups or regions. The results of the present study show that the KIR gene family is highly polymorphic and can be a valuable tool for enriching the Chinese ethnical gene information resources, for anthropological studies, as well as for KIR gene related disease research.

Five-year risk of colorectal neoplasia after normal baseline colonoscopy in asymptomatic Chinese Mongolian over 50 years of age

After normal colonoscopy, the 5-year risk of colorectal neoplasia is sufficiently low for asymptomatic people over 50years of age. In China, the incidence of colorectal carcinoma of Mongolian people is higher than that of Han people. The aim of this study was to assess the 5-year risk of colorectal neoplasia after normal colonoscopy in asymptomatic Chinese Mongolian population. A cohort of asymptomatic Chinese Mongolian people (≥50years old) were recruited and followed up with colonoscopy 5years after colonoscopy. Baseline colonoscopy and follow-up colonoscopy findings were categorized based on the most advanced lesions: no adenoma, nonadvanced adenoma, and advanced adenoma. Five-year risk of colorectal neoplasia in these people was assessed according to the rates of no baseline adenoma and advanced adenoma at the end of 5years. A total of 480 of the 538 recruited people underwent follow-up colonoscopy at the end of 5years. In people with no baseline adenoma, 27.3% (82/301) was found to have any adenoma, and 1.7% had advanced adenoma at follow-up colonoscopy. The risk of an advanced adenoma did not differ significantly between people with no adenoma at baseline and those with nonadvanced adenoma (relative risk (RR), 1.06; 95% confidence interval (CI), 0.19-6.07). Advanced adenoma at baseline colonoscopy was the independent risk factor for advanced adenoma recurrence, compared with no adenoma at baseline (RR, 8.25; 95% CI, 1.90-35.77). The risk of advanced adenoma is low 5years after the normal baseline colonoscopy, even in asymptomatic Chinese Mongolian population over 50years of age.

Interaction between the C(-344)T polymorphism of CYP11B2 and alcohol consumption on the risk of essential hypertension in a Chinese Mongolian population

The present study aimed to explore gene-gene and gene-environment interactions among three candidate genes and several environmental risk factors, and their impacts on hypertension in Chinese Mongolian population. A cross-sectional study was conducted in 2003-2004 among 1,575 Mongolian people in Tongliao City of Inner Mongolia, China. Epidemiologic and clinical data and blood samples were obtained from subjects. Multifactor dimensionality reduction (MDR) and logistic regression were used to analyze gene-gene and gene-environment interactions. The MDR model indicated a significant interactions among the CYP11B2 gene C(-344)T polymorphism, body mass index, age, and alcohol consumption on the risk of hypertension, with a cross-validation consistency of 10 of 10 and a prediction error of 34% (P < 0.001). Logistic regression suggested alcohol consumption (≥200 g/d) was associated with an OR of 2.4 (95% CI, 1.6-3.5) for hypertension. When stratified by the CYP11B2 genotype, the estimated OR was 1.2 (95% CI, 0.5-3.0) on hypertension for the CC genotype group, but was 3.0 (95% CI, 1.5-5.7) and 2.9 (95% CI, 1.4-5.7) for the TC and TT genotype groups, respectively. A significant interaction between the CYP11B2 genotype and alcohol consumption was also found by the logistic models (P (crude) = 0.035, P (adjusted) = 0.048). This study demonstrates a significant interaction between the CYP11B2 genotype and alcohol consumption on the risk of hypertension in Chinese Mongolian population.

Association of aldosterone synthase (CYP11B2) gene -344T/C polymorphism with essential hypertension in Mongolian nationality

To explore the relationship between the -344T/C polymorphism of aldosterone synthase (CYP11B2) gene and essential hypertension in Chinese Mongolian population. By cluster-sampling method, a total of 1575 Mongolian people in Tongliao city of Inner Mongolia were included in this study. And 417 subjects were normotension, 596 subjects were prehypertension and 562 subjects were essential hypertension. A survey was conducted to collect data by personal interview using a standard questionnaire, meanwhile fasting blood samples were drawn. Height, weight, waist circumference, blood pressure, blood-fat indexes and fasting plasma glucose were measured. The variant genotypes of CYP11B2 were identified by PCR assays. The relationship between the -344T/C polymorphism of CYP11B2 gene and essential hypertension were analyzed by multinomial logistic regression model. Crude prevalence of prehypertension among Mongolian people was 37.84% (596/1575) and hypertension was 35.68% (562/1575). The age-standardized prevalence of prehypertension was 38.57% and hypertension was 31.53%. The frequency of the T and C allele was 0.66 (481/728) and 0.34 (247/728) for normotension group, 0.69 (696/1042) and 0.33 (346/1042) for prehypertension group, 0.71 (706/998) and 0.29 (292/998) for hypertension group. The multiple logistic models showed CYP11B2 variant genotypes were associated with prehypertension (TT/CC, OR = 1.33, 95%CI: 0.87 - 2.01; TC/CC, OR = 1.74, 95%CI: 1.13 - 2.67; TC + TT/CC, OR = 1.49, 95%CI: 1.01 - 2.22); CYP11B2 variant genotypes were associated with hypertension (TT/CC, OR = 1.70, 95%CI: 1.07 - 2.70; TC/CC, OR = 1.59, 95%CI: 0.98 - 2.50; TC + TT/CC, OR = 1.66, 95%CI: 1.06 - 2.58). CYP11B2 gene -344T/C polymorphism were associated with essential hypertension in Chinese Mongolian population.

Interaction of the C-344T polymorphism of CYP11b2 gene with body mass index and waist circumference affecting diastolic blood pressure in Chinese Mongolian population

Background. The relationship between the C-344T polymorphism of CYP11b2 gene and blood pressure (BP) is controversial. The present study aimed to investigate whether it was affected by environmental determinants in Chinese Mongolian population. Methods. A cross-sectional study was conducted between 2003 and 2004 in Tongliao City of Inner Mongolia, China. Epidemiological and clinical data and blood samples were obtained from subjects. Multiple linear regression models were used to estimate the associations between the CYP11b2 genotype and BP. Results. In univariate model, the CYP11b2 genotype was associated with diastolic BP. When stratified by the body mass index (BMI) tertile, the estimated association was significant in the highest tertile of the BMI group with adjustment for age and gender (TT:β=3.3, p=0.042), but was not significant in the other tertiles. After multivariate adjustment, the estimated association was still significant only in highest tertile of BMI group (TC:β=3.7, p=0.030; TT:β=3.7, p=0.023). A similar pattern emerged in analyses stratified by the waist circumference (WC) tertile. Conclusion. In this study, the association between the CYP11b2 genotype and diastolic BP was modified by BMI and WC, suggesting an interaction of the C-344T polymorphism of CYP11b2 with BMI and WC in a Chinese Mongolian population.

Impact of gene-environment interaction between the C (-344) T polymorphism of CYP11B2 and drinking index on the risk of hypertension under multifactor dimensionality reduction model in Chinese Mongolian population

To explore the interaction between C (-344) T polymorphism of CYP11B2 and drinking index (DI) as well as their impact on the risk of hypertension in Chinese Mongolian population. A total of 1575 Mongolian people aged 20 and older including 562 hypertensive and 1013 normal-tensive from agricultural and pastoral areas in Tongliao city of Inner Mongolia, were included in this study. A cross-sectional survey was conducted to collect data by personal interview with local residents, using a standard questionnaire. Fasting blood samples were drawn and height, weight and blood pressure were measured. The variant genotypes of CYP11B2, ACE and eNOS were identified by PCR assays. Gene-environment interactions were analyzed, using multifactor dimensionality reduction (MDR) model. Based on the result of the best MDR model, a multiple logistic regression model was constructed as the final cause-effect interpretative model. The interaction between CYP11B2 variant genotype and drinking index appeared the best MDR model with statistical significance (chi(2) = 66.35, P < 0.01). Testing balance accuracy of the model was 0.604. The cross-validation consistency was 10/10. Data from the final multiple logistic regression based on the MDR model showed that the main effects of both CYP11B2 variant genotype and the DI were not significantly different but the interaction between the genotype (TC) and the DI (90-) was, with regard to hypertension (OR, 10.25; 95%CI, 2.23 - 47.18; P = 0.003). The combined effects between CYP11B2 variant genotype and the DI showed that following indices as: genotype TT or TC combining non-zero drinking index, including genotype (TT) combining the drinking index (> or = 168), the genotype (TT) combining the drinking index (> or = 40), the genotype (TT) combining the drinking index (> or = 1) and the genotype (TC) combining the drinking index (> or = 90), were all risk factors of hypertension when comparing with genotype (CC) combining the drinking index (0), and the ORs (95%CI) appeared to be 2.07 (1.15 - 3.70), 2.35 (1.22 - 4.56), 2.05 (1.07 - 3.94) and 5.56 (2.54 - 12.18) respectively. Essential hypertension might positively be affected by the interaction of the C (-344) T polymorphism of CYP11B2 and the drinking index in Chinese Mongolian population.