Efficient test for deviation from Hardy-Weinberg equilibrium with known or ambiguous typing in highly polymorphic loci.

The Hardy-Weinberg equilibrium (HWE) assumption is essential to many population genetics models. Multiple tests were developed to test its applicability in observed genotypes. Current methods are divided into exact tests applicable to small populations and a small number of alleles, and approximate goodness-of-fit tests. Existing tests cannot handle ambiguous typing in multi-allelic loci. We here present a novel exact test Unambiguous Multi Allelic Test (UMAT) not limited to the number of alleles and population size, based on a perturbative approach around the current observations. We show its accuracy in the detection of deviation from HWE. We then propose an additional model to handle ambiguous typing using either sampling into UMAT or a goodness-of-fit test test with a variance estimate taking ambiguity into account, named Asymptotic Statistical Test with Ambiguity (ASTA). We show the accuracy of ASTA and the possibility of detecting the source of deviation from HWE. We apply these tests to the HLA loci to reproduce multiple previously reported deviations from HWE, and a large number of new ones.

Semi-supervised machine learning method for predicting homogeneous ancestry groups to assess Hardy-Weinberg equilibrium in diverse whole-genome sequencing studies.

Large-scale, multi-ethnic whole-genome sequencing (WGS) studies, such as the National Human Genome Research Institute Genome Sequencing Program's Centers for Common Disease Genomics (CCDG), play an important role in increasing diversity for genetic research. Before performing association analyses, assessing Hardy-Weinberg equilibrium (HWE) is a crucial step in quality control procedures to remove low quality variants and ensure valid downstream analyses. Diverse WGS studies contain ancestrally heterogeneous samples; however, commonly used HWE methods assume that the samples are homogeneous. Therefore, directly applying these to the whole dataset can yield statistically invalid results. To account for this heterogeneity, HWE can be tested on subsets of samples that have genetically homogeneous ancestries and the results aggregated at each variant. To facilitate valid HWE subset testing, we developed a semi-supervised learning approach that predicts homogeneous ancestries based on the genotype. This method provides a convenient tool for estimating HWE in the presence of population structure and missing self-reported race and ethnicities in diverse WGS studies. In addition, assessing HWE within the homogeneous ancestries provides reliable HWE estimates that will directly benefit downstream analyses, including association analyses in WGS studies. We applied our proposed method on the CCDG dataset, predicting homogeneous genetic ancestry groups for 60,545 multi-ethnic WGS samples to assess HWE within each group.

Interleukin-6 (-174G/C), Interleukin-1ß (-511 C/T), and Apolipoprotein B-100 (2488 C/T) Gene Polymorphism in Pre-Eclampsia.

Background and objectives: Pre-eclampsia (PE) is a pregnancy-specific condition characterized by significant health risks for pregnant women worldwide due to its status as a multi-organ disorder. High blood pressure (hypertension) with or without proteinuria is usually considered an initial clinical sign of PE. The pathogenesis of pre-eclampsia is highly complex and likely involves multiple factors, including poorly developed uterine spiral arterioles, immunological issues, placental ischemia or infarction, and genetic abnormalities. Inflammatory cytokine production, regulated by cytokine gene polymorphisms, is one of the factors likely contributing to the development of PE. The present study aimed to assess IL-6, IL-1ß, and Apo B-100 gene polymorphism and to evaluate the association of these polymorphisms with PE. Materials and Methods: This cross-sectional observational study involved 99 participants aged 16 to 45 years from Bahawal Victoria Hospital Bahawalpur, Punjab, Pakistan. The participants were divided into three groups: Group 1 (PE with severe hypertension), Group 2 (PE with hypertension), and Group 3 (control), each comprising 33 individuals. Maternal blood samples were collected, DNA was extracted, and molecular genetic analysis of the IL-6, IL-1ß, and Apo B-100 genes was performed using the PCR-RFLP method. Allelic frequencies were compared, and statistical analysis was conducted using SPSS 25, applying the Hardy-Weinberg equation and chi-square test to evaluate the results. Results: There are differences in the distribution of allelic frequencies for IL-6 -174G/C (CC, GC, GG), IL-1ß-511C/T (CC, CT, TT), and Apo B-100 2488 C/T (CC, CT, TT) between pre-eclamptic patients and the control group. The analysis using the Hardy-Weinberg equilibrium and chi-square test showed an association between the IL-6-174 G/C polymorphism and the severity of pre-eclampsia. Conclusions: The polymorphisms of the IL-6, IL-1ß, and Apo B-100 genes revealed different alleles. The IL-6 gene alone was found to be in disequilibrium according to the Hardy-Weinberg equation, indicating a potential link to the severity of pre-eclampsia in the population studied.

Revealing of TLR-9 gene polymorphisms by qPCR HRM technique and their influence on TLR-9 serum level in acute myeloid leukemia patients: Case-control study.

Acute myeloid leukemia (AML) is one of the most common and fatal malignancies that affect adults, which can quickly become aggressive if left untreated, and leukemia cells invade the bone marrow. TLR-9 is an innate immune cell receptor sensitive to various PAMPs and encoded by the TLR-9 gene. As is often known, genetic polymorphisms in any gene can help the development of the disease, and these three polymorphisms, rs187084, rs5743836, and rs352140 of TLR-9, have been studied in many different cancer disorders. Therefore, this study aimed to discover the multiple forms of a TLR-9 gene in a sample of Iraqi AML patients. A total of 120 participants in a case-control study were enrolled in the current study. Using CBC, some hematological parameters were evaluated, and the serum level of TLR-9 was assessed using the ELISA technique. DNA was extracted directly from blood, and a high-resolution melting (HRM) analysis was then carried out. The results revealed a significant difference in some blood parameters among patients and healthy control, while WBC and lymphocytes were without an evident difference between the two groups of the current investigation. The serum concentration of TLR-9 showed an elevated level in patients (P value < 0.01). Nonetheless, this increase was not affected by the genotype patterns of polymorphisms. According to the P-value, there was a significant difference in wild genotypes of the three polymorphisms (rs187084, rs5743836, and rs352140). At the same time, the odds ratio revealed the association with the disease as a protective factor. In contrast, there was a significant difference in the heterozygous and mutant genotypes of TLR-9 polymorphisms, though the odds ratio confirmed the association with the AML as a risk factor. The results of rs352140 were compatible with H.W.E since there were no significant differences between the observed and expected values for either patients or healthy controls. In contrast, the result of rs5743836 was not consistent with the HWE. Furthermore, although it corresponds with the healthy one, the finding of rs187084 conflicted with H.W.E. in the patient group. In conclusion, High serum levels of TLR-9 in patients could act as biomarkers for AML. The TLR-9 gene polymorphisms (rs187084, rs5743836, and rs352140) have been linked to an increased risk of AML and may impact the disease progression in the Iraqi population.

Hardy-Weinberg Equilibrium in Meta-Analysis Studies and Large-Scale Genomic Sequencing Era.

The Hardy-Weinberg Equilibrium (HWE) is a fundamental principle employed in the analysis of genetic data, encompassing studies of meta-analysis and genomic sequencing. It has been demonstrated that HWE possesses the property of transitivity, wherein a multi-allelic polymorphism in equilibrium will persist in its equilibrium state even when alleles are deleted or combined. Nonetheless, the practice of filtering loci that do not adhere to HWE has been observed to impact the inference of population genetics within RADseq datasets. In response to this concern, the Robust Unified Test for HWE (RUTH) has been devised to consider population structure and genotype uncertainty, thereby offering a more precise evaluation of the quality of genotype data. Furthermore, deviations from HWE, such as extreme heterozygote excess, can be effectively utilized to identify genotyping errors or to pinpoint the presence of rare recessive disease-causing variants. In summary, it is evident that HWE holds immense significance in the field of genetic analysis, and its application in meta-analysis studies and genomic sequencing can yield invaluable insights into the intricacies of population structure and the genetics of diseases.

Single nucleotide variants in the CCL2, OAS1 and DPP9 genes and their association with the severity of COVID-19 in an Ecuadorian population.

COVID-19 has a broad clinical spectrum, ranging from asymptomatic-mild form to severe phenotype. The severity of COVID-19 is a complex trait influenced by various genetic and environmental factors. Ethnic differences have been observed in relation to COVID-19 severity during the pandemic. It is currently unknown whether genetic variations may contribute to the increased risk of severity observed in Latin-American individuals The aim of this study is to investigate the potential correlation between gene variants at CCL2, OAS1, and DPP9 genes and the severity of COVID-19 in a population from Quito, Ecuador. This observational case-control study was conducted at the Carrera de Biologia from the Universidad Central del Ecuador and the Hospital Quito Sur of the Instituto Ecuatoriano de Seguridad Social (Quito-SUR-IESS), Quito, Ecuador. Genotyping for gene variants at rs1024611 (A>G), rs10774671 (A>G), and rs10406145 (G>C) of CCL2, OAS1, and DPP9 genes was performed on 100 COVID-19 patients (43 with severe form and 57 asymptomatic-mild) using RFLP-PCR. The genotype distribution of all SNVs throughout the entire sample of 100 individuals showed Hardy Weinberg equilibrium (P=0.53, 0.35, and 0.4 for CCL2, OAS1, and DPP9, respectively). The HWE test did not find any statistically significant difference in genotype distribution between the study and control groups for any of the three SNVs. The multivariable logistic regression analysis showed that individuals with the GG of the CCL2 rs1024611 gene variant had an increased association with the severe COVID-19 phenotype in a recessive model (P = 0.0003, OR = 6.43, 95% CI 2.19-18.89) and for the OAS1 rs10774671 gene variant, the log-additive model showed a significant association with the severe phenotype of COVID-19 (P=0.0084, OR=3.85, 95% CI 1.33-11.12). Analysis of haplotype frequencies revealed that the coexistence of GAG at CCL2, OAS1, and DPP9 variants, respectively, in the same individual increased the presence of the severe COVID-19 phenotype (OR=2.273, 95% CI: 1.271-4.068, P=0.005305). The findings of the current study suggests that the ethnic background affects the allele and genotype frequencies of genes associated with the severity of COVID-19. The experience with COVID-19 has provided an opportunity to identify an ethnicity-based approach to recognize genetically high-risk individuals in different populations for emerging diseases.

Evaluation of Hardy-Weinberg equilibrium in genetic association studies.

STrengthening the REporting of Genetic Association (STREGA) studies strongly recommend that researchers assess the Hardy-Weinberg equilibrium (HWE) in their control groups. The exact frequency of studies in which their control subjects show a significant deviation from the HWE is not well established. Therefore, the present study was conducted. The electronic database PubMed was searched using the terms: 'meta-analysis' and 'polymorphism'. Data of original articles were extracted from meta-analysis. The STREGA statement was published in 2009. Therefore, studies were divided into two groups, before and after the statement. After data collection, quartiles for sample size and minor allele frequency (MAF) were determined separately. A total of 772 independent studies were extracted from these meta-analyses and included in the current study. Multivariate analysis revealed the following associations: (1) Reports published after the STREGA statement (compared to before the statement) were associated with an increased prevalence of deviation from HWE. (2) Reports with sample size Q2-Q4 versus Q1 were associated with an increased prevalence of deviation from HWE. (3) Studies with MAF Q4 versus Q1 were negatively associated with the prevalence of reports of deviation from HWE. We conclude that the STREGA statement failed to change the attitudes and practices of researchers and editors towards the importance of HWE.

Phenotype, allele and genotype frequency distribution of ABO and Rh(D) blood group among blood donors attending regional blood transfusion centre in Delhi, India.

The ABO and Rh blood group phenotypes, alleles, and genotype frequencies have many biological and medical implications. The frequency differs broadly according to races, geographical borders and ethnicity, even within the same region. This study was designed to determine the frequency of ABO and Rh blood groups among blood donors attending the regional blood transfusion centre in Delhi. The gel card method was used to determine the ABO and Rh(D) blood groups of donors who donated blood between January 1, 2020, and June 30, 2022. The assumption of Hardy-Weinberg equilibrium was used to determine allele and genotype frequencies of blood donors. A total of 16,925 blood units were donated during the study period. Donors phenotype frequencies of ABO were as follows: 'A' (23.88%), 'B' (37.38%), 'AB' (9.97%) and 'O '(29.27%). Rh(D)+Ve (D) were (94.9%) and Rh(D)-Ve (d) were (5.01%), which follow an order of B > O > A > AB and Rh-D > d for Rh. Donors ABO and Rh (D) allele frequencies were IA-0.183, IB-0.277, IO-0.541 and ID-0.776, Id-0.224 respectively. Allele frequencies follow an order of IO > IB > IA and Rh- ID > Id. Donors ABO genotype frequencies were AA-0.0333, AO-0.198, BB-0.0768, BO-0.30, AB-0.101, OO-0.293 and Rh(D) genotype frequencies were DD-0.602, Dd-0.347, dd-0.0501. Genotype frequencies follow an order of BO > OO > AO > AB > BB > AA and DD > Dd > dd. Among our donors, which were mostly from northern India, the ABO and Rh(D) blood groups have the highest proportion of ABO-B and Rh(D)+Ve and the lowest proportion of ABO-AB and Rh(D)-Ve, with a stable order of B > O > A > AB and D > d for phenotype, IO > IB > IA and ID > Id for allele and BO > OO > AO > AB > BB > AA and DD > Dd > dd for genotype.

Genetic analysis of polymorphism rs10937405 of TP63 gene in breast and ovarian cancer patients of North Indian Cohort.

Introduction: Ovarian and breast cancers are highly prevalent in the population of Jammu and Kashmir (J&K). However, case-control association studies on breast and ovarian cancers are lacking in this population. Moreover, no case-control study is available on variant rs10937405 of TP63 in breast and ovarian cancers. Thus, we designed to replicate the cancer susceptible variant rs10937405 of TP63 in ovarian and breast cancers in the population of J&K because the TP63 gene act as a tumor suppressor gene and was previously associated with various cancers. Materials and Methods: This case-control association study conducted at the Shri Mata Vaishno Devi University, includes 150 breast, 150 ovarian cancer cases, and 210 healthy controls (age and sex-matched). Variant rs10937405 of the TP63 gene was determined by the TaqMan assay. Hardy-Weinberg equilibrium for the variant was assessed using the Chi-square test. The allele and genotype-specific risks were estimated by odds ratios (ORs) with 95% confidence intervals (CI). Results: In this study, variant rs10937405 of TP63 gene did not show any risk with ovarian and breast cancer with (P-value = 0.70) having OR 0.94, (0.69-1.28 at 95% CI) and (P-value = 0.16) having OR 0.80, (0.59-1.10). Discussion: Our results indicate that the variant rs10937405 of the TP63 gene did not impart any risk of breast and ovarian cancer in the population of J&K. Our results indicate that a larger sample size is needed for further statistical validation. As the study was for a particular variant, it warrants the analysis of other variants of this gene.

Association of 2 Lysyl Oxidase Gene Single Nucleotide Polymorphisms with Keratoconus: A Nationwide Registration Study.

Purpose: Keratoconus (KC) is the most common primary ectatic corneal disease, characterized by progressive thinning of the cornea, affecting its shape and structure and leading to visual loss. Lysyl oxidase is an important component of the extracellular matrix and contributes to the homeostasis of corneal stromal extracellular matrix via enzymatic reaction. This nationwide registration study aims to examine the association of KC with 2 known single nucleotide polymorphisms, rs2956540 and rs10519694, in a population of Iranian descent. Design: Case-control. Participants: One hundred seventy-eight subjects with KC and 180 clinically healthy subjects participated in the study. Methods: Genomic DNA was extracted from peripheral blood samples, and their genotypes were determined using tetra-primer amplification refractory mutation system-polymerase chain reaction. Main Outcome Measures: Allele frequency for rs2956540 and rs10519694. Results: Genotype frequency was significantly different between cases and controls for rs2956540 (P value = 0.019). The rs2956540 C allele carriers were significantly more frequent among KC cases than healthy controls (P valuechi-square = 0.015, P valueFisher exact = 0.017). There was a significant difference in genotype frequency between groups for rs10519694 (P value = 0.001). T allele carriers were significantly more frequent among KC patients (P valuechi-square = 0.002, P valueFisher exact = 0.001). Sex stratification revealed no significant differences in genotype frequency between males and females in cases and controls. Fitting the general linear model showed that rs10519694 could be considered a predictor for the development of KC (P value = 0.001); however, this was not observed for rs2956540 (P value = 0.323). Conclusions: rs2956540 and rs10519694 are associated with KC in a population of Iranian descent. rs10519694 could potentially be used for KC risk prediction.

Genetic Analyses of Discrete Geographic Samples of a Golden Chanterelle in Canada Reveal Evidence for Recent Regional Differentiation.

The wild edible mushroom Cantharellus enelensis is a recently described species of the golden chanterelles found in eastern North America. At present, the genetic diversity and population structure of C. enelensis are not known. In this study, we analyzed a total of 230 fruiting bodies of C. enelensis that were collected from three regions of Canada: near the east and west coasts of Newfoundland (NFLD), with 110 fruiting bodies each, and around Hamilton, Ontario (10 fruiting bodies). Among the 110 fruiting bodies from each coast in NFLD, 10 from 2009 were without specific site information, while 100 sampled in 2010 were from each of five patches separated by at least 100 m from each other. Each fruiting body was genotyped at three microsatellite loci. Among the total 28 multilocus genotypes (MLGs) identified, 2 were shared among all three regions, 4 were shared between 2 of the 3 regions, and the remaining 22 were each found in only 1 region. Minimal spanning network analyses revealed several region-specific MLG clusters, consistent with geographic specific mutation and expansion. Though the most frequently observed MLGs were shared among local (patch) and regional populations, population genetic analyses revealed that both local and regional geographic separations contributed significantly to the observed genetic variation in the total sample. All three regional populations showed excess heterozygosity; for the eastern NFLD population, we reject the null hypothesis of Hardy-Weinberg equilibrium (HWE) at all three loci. However, the analyses of clone-corrected samples revealed that most loci were in HWE. Together, our results suggest that the three discrete regional populations of C. enelensis were likely colonized from a common refugium since the last ice age. However, the local and regional populations are diverging from each other through mutation, drift, and selection at least partly due to heterozygous advantage.

Linear Mixed-Effect Models Through the Lens of Hardy-Weinberg Disequilibrium.

For genetic association studies with related individuals, the linear mixed-effect model is the most commonly used method. In this report, we show that contrary to the popular belief, this standard method can be sensitive to departure from Hardy-Weinberg equilibrium (i.e., Hardy-Weinberg disequilibrium) at the causal SNPs in two ways. First, when the trait heritability is treated as a nuisance parameter, although the association test has correct type I error control, the resulting heritability estimate can be biased, often upward, in the presence of Hardy-Weinberg disequilibrium. Second, if the true heritability is used in the linear mixed-effect model, then the corresponding association test can be biased in the presence of Hardy-Weinberg disequilibrium. We provide some analytical insights along with supporting empirical results from simulation and application studies.

The transitivity of the Hardy-Weinberg law.

The Hardy-Weinberg law is shown to be transitive in the sense that a multi-allelic polymorphism that is in equilibrium will retain its equilibrium status if any allele together with its corresponding genotypes is deleted from the population. Similarly, the transitivity principle also applies if alleles are joined, which leads to the summation of allele frequencies and their corresponding genotype frequencies. These basic polymorphism properties are intuitive, but they have apparently not been formalized or investigated. This article provides a straightforward proof of the transitivity principle, and its usefulness in genetic data analysis is explored, using high-quality autosomal microsatellite databases from the US National Institute of Standards and Technology. We address the reduction of multi-allelic polymorphisms to variants with fewer alleles, two in the limit. Equilibrium test results obtained with the original and reduced polymorphisms are generally observed to be coherent, in particular when results obtained with length-based and sequence-based microsatellites are compared. We exploit the transitivity principle in order to identify disequilibrium-related alleles, and show its usefulness for detecting population substructure and genotyping problems that relate to null alleles and allele imbalance.

Associations between genetic variations in microRNA and myocardial infarction susceptibility: a meta-analysis and systematic review.

BACKGROUND: Current genetic association studies have reported conflicting results regarding the association between miRNA polymorphisms and myocardial infarction (MI) risk METHODS: Relevant studies were retrieved from the PubMed, EMBASE, ISI Web of Science, and Scopus databases. Eligible studies determining the association between miRNA polymorphisms and MI susceptibility were included and a meta-analysis was performed to quantify the associations between miRNA polymorphisms and MI risk. RESULTS: A total of eight studies with 2507 MI patients and 3796 healthy controls were included, dealing with nine miRNA genes containing 11 different loci, including miR-149 (rs71428439 and rs2292832), miR-126 (rs4636297 and rs1140713), miR-146a (rs2910164), miR-218 (rs11134527), miR-196a2 (rs11614913), miR-499 (rs3746444), miR-27a (rs895819), miR-26a­1 (rs7372209), and miR-100 (rs1834306). miR-146a rs2910164 and miR-499 rs3746444 were determined to have a significant association with MI susceptibility, a finding that was supported by the meta-analysis (rs2910164: GG/CC, odds ratio [OR]: 1.40, 95% confidence interval [95% CI]: 1.05-1.74, p < 0.001; rs3746444: AA + AG/GG, OR = 2.04, 95% CI: 1.37-2.70, p < 0.001). Limited or conflicting data were found for the relationship between the other miRNA polymorphisms (rs71428439, rs4636297, rs1140713, rs11134527, rs11614913, rs895819, rs7372209, rs1834306, rs2292832) and MI risk. CONCLUSION: There was a significant association between rs2910164 and rs3746444 and MI susceptibility. Further studies are required to investigate the role of miRNA polymorphisms in MI risk.

Vitamin D receptor gene polymorphisms and risk of breast cancer in Iranian women.

OBJECTIVES: Vitamin D deficiency is a driving force of common cancers like breast cancer. Vitamin D receptor (VDR) can play a tumor suppressor role by helping the precise function of vitamin D in cells such as modulation TGF-ß signaling pathway. This study aimed to investigate the association of VDR gene variants and susceptibility to breast cancer in Iranian women. METHODS: Genomic DNAs were isolated from blood samples of 161 women with breast cancer and 150 healthy women. After amplification of five positions of VDR gene, the prepared amplicons were digested with TaqI, ApaI, BsmI, Cdx2, and FokI restriction enzymes. RESULTS: Subsequently, the digested products were electrophoresed on the 1.5% agarose gel. Odds ratios (ORs) for breast cancer were calculated for genotypes and estimated haplotypes. Binary logistic regression analysis showed FokI (rs2228570), BsmI (rs1544410), and ApaI (rs7975232) polymorphisms had the significant distribution in patients than to the normal group. Analysis of linkage disequilibrium for all pairs of SNPs showed that D'-value between SNP TaqI and SNP BsmI was significantly (p ≤ 0.05). We observed that four major haplotypes of ApaI, BsmI, FokI, Cdx2, and TaqI SNPs significantly were in high frequency than predicted frequency. Among these four haplotypes, CGTAT haplotype was in a higher significant association than others with breast cancer risk (p-value = 0.0001). CONCLUSION: Our results showed that FokI, BsmI, and ApaI of VDR polymorphisms associated with the risk of breast cancer in Iranian population.

A generalized robust allele-based genetic association test.

The allele-based association test, comparing allele frequency difference between case and control groups, is locally most powerful. However, application of the classical allelic test is limited in practice, because the method is sensitive to the Hardy-Weinberg equilibrium (HWE) assumption, not applicable to continuous traits, and not easy to account for covariate effect or sample correlation. To develop a generalized robust allelic test, we propose a new allele-based regression model with individual allele as the response variable. We show that the score test statistic derived from this robust and unifying regression framework contains a correction factor that explicitly adjusts for potential departure from HWE and encompasses the classical allelic test as a special case. When the trait of interest is continuous, the corresponding allelic test evaluates a weighted difference between individual-level allele frequency estimate and sample estimate where the weight is proportional to an individual's trait value, and the test remains valid under Y-dependent sampling. Finally, the proposed allele-based method can analyze multiple (continuous or binary) phenotypes simultaneously and multiallelic genetic markers, while accounting for covariate effect, sample correlation, and population heterogeneity. To support our analytical findings, we provide empirical evidence from both simulation and application studies.

Dissecting the contribution of single nucleotide polymorphisms in CCR9 and CCL25 genomic regions to the celiac disease phenotype.

PURPOSE AND OBJECTIVES: Given their role in homing immune cells to the intestine, CC motif chemokine receptor 9 (CCR9) and its specific ligand CC motif chemokine ligand 25 (CCL25) are interesting candidate genes for celiac disease. These genes are located in regions previously shown to be associated with or linked to celiac disease, but no investigations on their association with various celiac disease phenotypes have so far been conducted. Here we studied such associations of both genotyped and imputed single nucleotide polymorphisms (SNPs) with either regulatory function or exonic location of the CCR9 and CCL25 loci. RESULTS: Exploiting a carefully phenotyped cohort of 625 celiac disease patients and 1817 non-celiac controls, we identified that multiple SNPs with predicted regulatory function (RegulomeDB score ≤3a and/or eQTL effect) located between 100 kB upstream and downstream of CCR9 and CCL25 are associated with celiac disease and/or selected phenotypes. Of the genotyped SNPs in the CCR9 loci, rs213360 with an eQTL effect on CCR9 expression in blood was associated with celiac disease and all investigated phenotypes except high HLA risk. Rs1545985 with an eQTL on CCR9 expression and rs7652331 and rs12493471, both with RegulomeDB score ≤3a, were all associated with gastrointestinal symptoms and malabsorption and the latter additionally with anemia. The genotyped CCL25 SNPs rs952444 and rs882951, with RegulomeDB scores 1d and 1f respectively and eQTL effect on CCL25 expression in small intestine, were associated with gastrointestinal symptoms and malabsorption. The CCL25 SNP rs2303165 identified in sequencing followed by imputation was associated with partial villous atrophy. However, the association did not pass the permutation based multiple testing correction (PEMP2 > 0.05). CONCLUSIONS: We conclude that SNPs in the region of CCR9 and CCL25 with predicted functional effect or exonic localization likely contribute only modestly to various celiac disease phenotypes.

Biological and Clinical Implications of TNF-α Promoter and CYP1B1 Gene Variations in Coronary Artery Disease Susceptibility.

BACKGROUND: Cardiovascular diseases (CVD) are important causes of death worldwide. Atherosclerosis is a chronic inflammatory disorder. It is the major cause of CVD and is manifested by ischemic heart disease or coronary artery disease (CAD). TNF-α is a pro-inflammatory cytokine that regulates immune response and promotes the development of atherosclerosis. Cytochrome p450 1B1 (CYP1B1) is an enzyme involved in the metabolism of endogenous and exogenous substrates. OBJECTIVES: This study aimed at examining the association of TNF-α rs1800629 G>A and CYP1B1 rs1056827 G>T gene polymorphisms with CAD susceptibility in an Indian cohort. METHODS: AS-PCR and direct DNA sequencing were used to examine the association of TNF-α rs1800629 G >A and CYP1B1 rs1056827 G>T gene polymorphism with CAD in an Indian cohort. A total of 100 clinically confirmed cases of CAD and 110 matched apparently healthy controls were genotyped. RESULTS: Allelic and genotypic frequencies did not deviate from Hardy-Weinberg equilibrium in the controls (p>0.05) for TNF-α G-308A and CYP1B1 rs1056827G>A. There was no significant difference between the TNF-α rs1800629 A>G genotype distribution between cases and controls (P-value >0.05). A significant difference was observed between the CYP1B1 rs1056827 G>T genotype distribution between CAD cases and controls (p<0.0003). Our result indicated that in the codominant model, the GA genotype of the CYP1B1 rs1056827 G>T was associated with CAD with OR= 2.21(1.17 to 4.15), RR=1.38(1.07 to 1.78), and p<0.013. In the dominant model, the (GA+AA) genotype was associated with CAD with OR=2.79(1.54 to 5.05) and p<0.007. The CYP1B1 rs1056827 'A' allele was associated with CAD with OR = 2.30 (1.55 to 3.42) and p< 0.0001. Our results indicated that TNF-α 1800629 gene polymorphism was strongly associated with hypercholesteremia (p<0.0009), HDL (p<0.0001), TGL (p<0.039), hypertension (p<0.0001), and smoking (p<0.0001) in patients with Coronary Artery Disease. Similar correlations of CYP1B1 rs1056827 genotypes were reported with cholesterol (p<0.020), HDL (p<0.002), LDL (p<0.006), hypertension (p<0.03), and smoking (p<0.005). CONCLUSION: It was reported that the GA genotype of the CYP1B1 rs1056827 G>T was strongly associated with susceptibility to Coronary Artery Disease with OR= 2.21(1.17 to 4.15)) and p<0.013, and similarly, its A allele was associated with predisposition to CAD with OR = 2.30 (1.55 to 3.42) and p< 0.0001. Our results indicated that TNF-α 1800629 gene polymorphism is not associated with predisposition to Coronary Artery Disease. Nevertheless, these results should be taken with caution and further validated with larger-scale studies before being introduced in the clinical setting.

Diversity, Dispersal and Mode of Reproduction of Amanita exitialis in Southern China.

Amanita exitialis is a poisonous mushroom and has caused many deaths in southern China. In this study, we collected 118 fruiting bodies of A. exitialis from seven different sites in Guangdong Province in southern China and investigated their genetic relationships using 14 polymorphic molecular markers. These 14 markers grouped the 118 fruiting bodies into 20 multilocus genotypes. Among these 20 genotypes, eight were each found only once while the remaining 12 were each represented by two to 54 fruiting bodies. Interestingly, among the 12 shared genotypes, four were shared between/among local populations that were separated by as far as over 80 km, a result consistent with secondary homothallic reproduction and long-distance spore dispersal. Despite the observed gene flow, significant genetic differentiations were found among the local populations, primarily due to the over-representation of certain genotypes within individual local populations. STRUCTURE analyses revealed that the 118 fruiting bodies belonged to three genetic clusters, consistent with divergence within this species in this geographic region. Interestingly, we found an excess of heterozygous individuals at both the local and the total sample level, suggesting potential inbreeding depression and heterozygous advantage in these populations of A. exitialis. We discuss the implications of our results for understanding the life cycle, dispersal, and evolution of this poisonous mushroom.