HLA-G Gene Polymorphism Research Articles

Relationships Between Polymorphisms in HLA-G 3'UTR Region and COVID-19 Disease Severity.

The objective of this study is to investigate the the relationships between HLA-G gene variants and sHLA-G with susceptibility to SARS-CoV-2 infection. In this case-control study, 65 Patients with COVID-19 were and 67 healthy controls were genotyped for their main functional polymorphisms namely, the 14-bp Ins/Del (rs371194629), +3003C/T (rs1707), +3010C/G (rs1710), +3027A/C (rs17179101), +3035C/T (rs17179108), +3142C/G (rs1063320), +3187A/G (rs9380142) and +3196C/G (rs1610696) in the exon 8 of the 3' untranslated regions (3' UTRs) using sanger sequencing method. Associations were assessed for five inheritance models (codominant, dominant, recessive, over-dominant and log-additive). Moreover, the levels of plasma soluble HLA-G (sHLA-G) were explored using ELISA method. Our results revealed that the 14-bp INS/DEL polymorphism was strongly associated with COVID-19 symptoms development for almost all tested inheritance models (p < 0.001). Inversely, the (+3196C/G) polymorphism exhibited a protective effect against COVID-19. In addition, three haplotypes; UTR-1, UTR-3, and UTR-5 were found associated with COVID-19 symptoms (p < 0.05), The level of HLA-G in the serum was significantly higher in COVID-19 individuals than in healthy individuals (p < 0.001).These findings suggest that HLA-G gene polymorphisms in the regulatory 3'UTR region of the HLA-G gene may influence the host immune response to SARS-CoV-2 infection. A deeper comprehension of the functional effect of these associated polymorphisms could be useful in identifying high-risk individuals and in developing adaptive treatments for patients.

Decision trees for early prediction of inadequate immune response to coronavirus infections: a pilot study on COVID-19.

Few artificial intelligence models exist to predict severe forms of COVID-19. Most rely on post-infection laboratory data, hindering early treatment for high-risk individuals. This study developed a machine learning model to predict inherent risk of severe symptoms after contracting SARS-CoV-2. Using a Decision Tree trained on 153 Alpha variant patients, demographic, clinical and immunogenetic markers were considered. Model performance was assessed on Alpha and Delta variant datasets. Key risk factors included age, gender, absence of KIR2DS2 gene (alone or with HLA-C C1 group alleles), presence of 14-bp polymorphism in HLA-G gene, presence of KIR2DS5 gene, and presence of KIR telomeric region A/A. The model achieved 83.01% accuracy for Alpha variant and 78.57% for Delta variant, with True Positive Rates of 80.82 and 77.78%, and True Negative Rates of 85.00% and 79.17%, respectively. The model showed high sensitivity in identifying individuals at risk. The present study demonstrates the potential of AI algorithms, combined with demographic, epidemiologic, and immunogenetic data, in identifying individuals at high risk of severe COVID-19 and facilitating early treatment. Further studies are required for routine clinical integration.

HLA-G susceptibility to hepatitis B infection and related hepatocellular carcinoma in the Japanese population

AimsHuman leukocyte antigen (HLA)-G plays a role in various physiological immunomodulatory functions. Aberrant HLA-G expression is observed in various disease states, including tumors, autoimmune disorders, and viral infections. The present study investigated the association between HLA-G functional gene polymorphisms (rs1736933 [-486 C > A], rs1049033 [+2018 C > T], 14 bp Insertion [Ins]/Deletion [Del] [+2961 Del > Ins], and rs1063320 [+3142 C > G]) and disease susceptibility, hepatocellular carcinoma (HCC) development, and hepatitis B surface antigen (HBsAg) clearance. MethodsAllele discrimination of the 3 SNPs (-486 C > A, +2018 C > T, +3142 C > G) was determined by a TaqMan 5′ exonuclease assay, while the 14 bp Ins/Del polymorphism was typed by fragment analysis using Genetic Analyzer and GeneMapper software. The above polymorphisms were analyzed for 325 Japanese hepatitis B virus (HBV) patients, 355 Japanese healthy subjects (Controls) as healthy controls, and 799 Japanese hepatitis C virus (HCV) patients as disease controls, respectively. ResultsThe 14 bp Insertion allele was significantly more frequent in HBV patients than Controls (27.1 % vs 20.6 %, odds ratio [OR] 1.43, P = 0.005) but did not differ between HCV patients and Controls. Similar results were found for the rs1063320 G allele (38.9 % vs 26.3 %, OR 1.78, P < 0.001) and the rs1736933 T allele (32.2 % vs 26.9 %, OR 1.29, P = 0.034) between HBV and Controls. The rs1049033 T allele showed a weak but significant association with HCC development in the dominant model (OR 1.95, P = 0.04). Regarding HBsAg clearance, the A allele at rs1736933 was significantly correlated in the recessive model (OR 3.23, P = 0.003). ConclusionsThis study revealed significant associations of HLA-G gene polymorphisms with disease susceptibility, HCC development, and HBsAg clearance in HBV patients.

Understanding Health Disparities in Preeclampsia: A Literature Review.

Preeclampsia is a multifactorial pathology with negative outcomes in affected patients in both the peripartum and postpartum period. Black patients in the United States, when compared to their White and Hispanic counterparts, have higher rates of preeclampsia. This article aims to review the current literature to investigate how race, social determinants of health, and genetic profiles influence the prevalence and outcomes of patients with preeclampsia. Published studies utilized in this review were identified through PubMed using authors' topic knowledge and a focused search through a Medline search strategy. These articles were thoroughly reviewed to explore the contributing biosocial factors, genes/biomarkers, as well as negative outcomes associated with disparate rates of preeclampsia. Increased rates of contributing comorbidities, including hypertension and obesity, which are largely associated with low access to care in Black patient populations lead to disparate rates of preeclampsia in this population. Limited research shows an association between increased rate of preeclampsia in Black patients and specific APOL1, HLA-G, and PP13 gene polymorphisms as well as factor V Leiden mutations. Further research is required to understand the use of certain biomarkers in predicting preeclampsia within racial populations. Understanding contributing biosocial factors and identifying genes that may predispose high-risk populations may help to address the disparate rates of preeclampsia in Black patients as described in this review. Further research is required to understand if serum, placental, or urine biomarkers may be used to predict individuals at risk of developing preeclampsia in pregnancy. KEY POINTS: · Prevalence of preeclampsia in the U.S. is higher in Black patients compared to other racial groups.. · Patients with preeclampsia are at risk for poorer health outcomes both during and after delivery.. · Limited research suggests specific biomarkers or gene polymorphisms contribute to this difference; however, explanations for this disparity are multifactorial and further investigation is necessary..

Association of HLA-G (rs1063320) gene polymorphism with recurrent pregnancy loss

Recurrent abortion, or miscarriage, is defined as pregnancy loss before 20 weeks’ gestation and is different from infertility. Commonly two or more pregnancies are lost spontaneously. The human leukocyte antigen (HLA) has been linked to many diseases. The HLA-G gene polymorphism may have an impact on pregnancy outcome. Objective. To study the association between the HLA-G (rs1063320) gene polymorphism and recurrent pregnancy loss (RPL). Patients and methods. This study included 100 women with RPL aged 20 to 45 years (a study group) and 50 age-matched healthy women with at least two successful pregnancies and normal blood pressure (a control group). Women with normal blood pressure, endocrine disorders, infections, and anatomical defects were excluded from the study group. All samples and data related to the studied cases were obtained from private clinics of genealogists between 2019 and 2022. Peripheral blood samples were obtained from patients and healthy controls. DNA extraction was done using the Promega Extraction Kit. PCR was then performed using the Amplification Refractory Mutation System (ARMS) to amplify the gene region specific for the HLA-G (rs1063320) single nucleotide polymorphism (SNP). Results. The frequency of CG, GG, and CC alleles was higher in women with RPL than in healthy controls. The frequency of CG allele in the study group was 18% compared to 8% in the control group, which was statistically significant (p &lt; 0.05). Conclusion. A high association was found between the HLA-G (rs1063320) gene polymorphism and RPL. Key words: HLA-G, polymorphism, recurrent pregnancy loss, SNP, ARMS-PCR

Study of HLA-G gene polymorphism and serum level of soluble HLA-G in patients infected with Mycobacterium tuberculosis

Tuberculosis affects about one-third of the world population. The incidence of the disease differs significantly among populations living under almost similar conditions, indicating the role of genetic factors. The present study aimed to appraise the impact of HLA-G gene polymorphisms and soluble HLA-G on the susceptibility to pulmonary tuberculosis. 48 patients with pulmonary tuberculosis and other 42 age- and sex-matched healthy individuals were included in the study. Both groups evaluated two gene polymorphisms in the HLA-G gene and soluble HLA-G protein. The frequency of Del/Del genotype of rs66554220 (14-bp Ins/Del) polymorphism in patients was 8.33% which was higher than that of controls (2.38%) with a significant difference (crude OR= 9.26, 95%CI=1.06-80.93, p=0.044). Such association remained significant after adjusting for confounding factors, including smoking, family history, socioeconomic status and residence (adjusted OR= 11.83, 95%CI=2.77-50.51, p= 0.01). The median serum level of soluble HLA-G in patients was 34.0 ng/ml (range 6.18-74.25 ng/ml), which was greater than that of controls (median 20 ng/ml, range 312-71.98 ng/ml) with a significant difference. We can conclude that The Del/Del genotype of rs66554220 (14-bp Ins/Del) polymorphism is an independent risk factor for pulmonary tuberculosis in the Iraqi population Keywords: Mycobacterium tuberculosis, HLA-G gene, single nucleotide polymorphism

The Effects of HLA-G Gene Polymorphism and sHLA-G Level in Women with Threatened Abortion

The most frequent first-trimester problem is a miscarriage, which affects 20% of pregnancies. In approximately 20-25 percent of confirmed pregnancies, threatened miscarriage is indeed a risk factor that may develop or resolve. This study aimed to assess the impact of certain HLA-G gene SNPs and sHLA-G serum levels to determine whether they play a role in threatening abortions. This study included 90 subjects who were separated into three groups: 30 patients (threatened abortion patients), and 60 controls (30 healthy pregnant women and 30 healthy non-pregnant women). All of the study groups were between the ages of 20 and 35 years old. The mean sHLA-G level in pregnant women's sera was found to be 430.38 Pg/ml, compared to 307.98 Pg/ml in the threatened abortion group and 192.11 Pg/ml in non-pregnant women (P= 0.001). The rs2249863 T/C/G was a statistically significant difference between the T allele and the G allele, with an odds ratio of 1.720 (p-value = 0.038). In conclusion, serum sHLA-G levels in threatened abortion patients' sera are significantly lower than in normal pregnant women. Allele frequencies of HLA-G gene snps were non-significant changes between TA patients and controls, except rs2249863 T/C/G.

3′UTR-HLA-G polymorphisms and circulating sHLA-G are associated with breast cancer: Evidence from a meta-analysis

BackgroundHuman leukocyte antigen-G (HLA-G) gene polymorphisms and circulating sHLA-G have often been linked to the risk of breast cancer (BC). However, the results remain controversial. To resolve this issue, we performed a meta-analysis of HLA-G gene polymorphisms and sHLA-G levels in BC. MethodsWe performed a meta-analysis on the association of HLA-G 14-bp Insertion/Deletion (Ins/Del) and HLA-G +3142 C/G polymorphisms with BC as well as the relationship between sHLA-G and the disease outcome. ResultsPooled analysis showed a statistically significant association between the HLA-G 14-bp Ins/Del polymorphism and BC susceptibility for the overall population and for Caucasians. The Del allele and genotypes with at least one copy of the Del allele presented significant risks for BC. For HLA-G +3142 C/G polymorphism, the G allele significantly decreased the risk of BC for the overall population and for Caucasians, indicating that the G allele was a protective factor against BC and that the C allele was a significant risk factor for BC. The meta-analysis revealed a significantly increased level of sHLA-G patients with BC compared to the control group for the overall population, Caucasians and Asians. ConclusionThe present meta-analysis showed a major association of both HLA-G 14-bp Ins/Del and +3142 C/G polymorphisms with BC susceptibility, suggesting Del and C variants as highly significant risk factors for BC. The present study also showed significantly higher sHLA-G levels in patients with BC compared to healthy controls. Our pooled results suggested a critical role of HLA-G in BC, thereby providing evidence to use HLA-G as a biomarker and a therapeutic tool.

Investigation of the association between HLA-G polymorphisms and obesity

Background/Aim: Obesity is a global public health problem seen worldwide, with an increasing prevalence over time. Obesity is a multifactorial disease affected by both genetic and environmental factors. It is accompanied by many other diseases, the most important of which are immune system disorders. Induction of suppression of HLA-G molecule T and B lymphocytes is associated with natural killer cells and antigen-presenting cells. The HLA-G gene shows functional polymorphisms in regulatory regions. The HLA-G gene is slightly more conserved compared to other HLA genes, both in the same population and among different populations. The aim of this research is to determine the association of HLA-G gene polymorphisms (14 bp insertion/deletion 3 'UTR (rs66554220), rs41557518, and rs1063320) with obesity. Methods: Fifty normal (BMI ≤30) individuals having no obesity-related chronic disorder, and 50 obese (BMI≥ 30) individuals were included in the study. After DNA isolation, PCR and PCR-RFLP methods were used for genotyping. Results: The genotype frequencies of HLA-G polymorphisms (rs66554220, rs41557518, and rs1063320) in the normal and obese groups were compared, and as a result, no significant difference was found (P>0.05). Conclusion: No significant association was found between rs66554220, rs41557518, and rs1063320 polymorphisms and obesity.

HLA Class Ib-receptor interactions during embryo implantation and early pregnancy.

Although the immune system intuitively must have an important role in embryo implantation and in the achievement of a pregnancy, the molecular details have for long been controversial. The role of the human leukocyte antigen (HLA) system has been debated. The unique HLA expression profile of the HLA Class Ia molecule HLA-C and the HLA Class Ib molecules HLA-E, HLA-F and HLA-G at the feto-maternal interface is now recognized. However, HLA Class Ib molecules may also have a role in embryo implantation and pregnancy success. The aim of this review was to evaluate the literature and recent discoveries on the role of the non-polymorphic HLA Class Ib molecules with a focus on HLA-F and HLA-G molecules at the time of implantation, including the interaction with uterine immune cells through the specific receptors immunoglobulin-like transcript 2 (ILT2), ILT4 and a number of killer cell immunoglobulin-like receptors (KIRs), and the importance of HLA-F and HLA-G genetic variation that influences fertility and time-to-pregnancy. Drawing on recent advances in basic and clinical studies, we performed a narrative review of the scientific literature to provide a timely update on the role of HLA Class Ib in embryo implantation, fertility and infertility. Pertinent studies were searched in PubMed/Medline using relevant key words. Both HLA-F and HLA-G interact with inhibitory or activating ILT2 or ILT4 receptors and KIRs on uterine immune cells, especially uterine natural killer (NK) cells that are highly abundant in the mid-secretory endometrium and in early pregnancy. The binding of HLA-G to ILT2 stimulates the secretion of growth-promoting factors from decidual NK cells. However, functional aspects of a HLA-F-receptor interaction remain to be clarified. Recent studies indicate that HLA-F and HLA-G are expressed in mid-secretory endometrium and HLA-G is expressed in the blastocyst. HLA-F fluctuates during the menstrual cycle with high levels during the implantation window. The level of HLA-F protein expression correlates with the number of CD56-positive NK cells in the mid-secretory endometrium. HLA-F and HLA-G gene polymorphisms, including a single nucleotide polymorphism (SNP) in a progesterone-responsive element, are associated with time-to-pregnancy. Depending on the SNP genotype, the effect of progesterone varies resulting in differences in HLA-F expression and thereby the interaction with receptors on the uterine NK cells. Studies suggest that the expression of HLA-G and HLA-F, both by the embryonic-derived trophoblast cells and by cells in the endometrium and decidua, and the interaction between HLA-G and HLA-F with specific receptors on uterine immune cells, stimulate and facilitate embryo implantation and placentation by secretion of growth factors, cytokines and angiogenic factors. A detailed understanding of the molecular mechanisms controlling the expression of HLA-F and HLA-G periconceptionally and in early pregnancy may improve the success of ART and holds promise for further insight into pathophysiological aspects of certain pregnancy complications.

The Association of HLA-G Gene Polymorphism and Its Soluble Form With Male Infertility.

Successful reproduction depends on many factors. Male factors contribute to infertility in approximately 50% of couples who fail to conceive. Seminal plasma consists of secretions from different accessory glands containing a mixture of various cytokines, chemokines, and growth factors, which together can induce a local immune response that might impact on a male’s as well as a female’s fertility. Human leukocyte antigen (HLA)-G expression has been suggested as an immunomodulatory molecule that influences pregnancy outcome. The HLA-G gene encodes either membrane-bound or/and soluble proteins. The aim of this study was the evaluation of HLA-G polymorphisms and their impact on soluble HLA-G (sHLA-G) production. We tested the HLA-G polymorphism in three positions: rs1632947: c.-964G>A; rs1233334: c.-725G>C/T in the promoter region; rs371194629: c.∗65_∗66insATTTGTTCATGCCT in the 3′ untranslated region. We tested two cohorts of men: 663 who participated in in vitro fertilization (test material was blood or sperm), and 320 fertile controls who possessed children born after natural conception (test material was blood). Since 50% of men visiting assisted reproductive clinics have abnormal semen parameters, we wondered if men with normal sperm parameters differ from those with abnormal parameters in terms of HLA-G polymorphism and secretion of sHLA-G into semen. We found that certain rs1632947-rs1233334-rs371194629 HLA-G haplotypes and diplotypes were associated with male infertility, while others were protective. Normozoospermic men with the A-C-del haplotype and A-C-del/A-C-del diplotype secreted the most sHLA-G into semen (574.1 IU/mL and 1047.0 IU/mL, respectively), while those with the G-C-ins haplotype and G-C-ins/G-C-ins diplotype – the least (80.8 IU/mL and 75.7 IU/mL, respectively). Men with the remaining haplotypes/diplotypes secreted sHLA-G at an intermediate level. However, only in one haplotype, namely G-C-ins, did we observe strong significant differences in the concentration of sHLA-G in the semen of men with teratozoospermia compared to men with normal sperm parameters (p = 0.009). In conclusion, fertile men differ in the profile of HLA-G polymorphism from men participating in IVF. Among all HLA-G haplotypes, the most unfavorable for male fertility is the G-C-ins haplotype, which determines the secretion of the lowest concentration of the soluble HLA-G molecule. This haplotype may reduce sperm parameters.

HLA-G 3'UTR polymorphisms & response to a yoga-based lifestyle intervention in rheumatoid arthritis: A randomized controlled trial.

Human leucocyte antigen (HLA)-G plays a vital role in immunomodulation in rheumatoid arthritis (RA). The mounting evidence suggests a link between HLA-G gene polymorphisms, disease susceptibility and methotrexate treatment response. Various environmental factors influence the onset and progression of RA and its treatment outcomes. The aim is to identify the treatment response of HLA-G 3' untranslated region polymorphisms to yoga-based lifestyle intervention (YBLI). In this eight-week single-blinded randomized controlled trial (CTRI/2017/05/008589), patients with RA (n=140) were randomized into two groups namely, yoga group or non-yoga group. Baseline genomic DNA was isolated using salting-out method. PCR-based methods were used for genotyping. The levels of soluble (s) HLA-G and disease activity were assessed by ELISA and disease activity score-28-erythrocyte sedimentation rate (DAS28-ESR), respectively, at baseline (day 0) and after eight weeks of intervention. Low-producing sHLA-G genotypes, i.e. +3142GG and 14 bp ins/ins, showed a significant increase in sHLA-G levels after YBLI. The association analysis between HLA-G polymorphisms and treatment for RA showed no considerable differential treatment remission in either of the groups (P>0.05). The percentages of improvement were higher in the yoga group as compared to the non-yoga group in both the HLA-G +3142G>C and 14 bp ins/del polymorphisms irrespective of their respective genotypes. No significant association was found between sHLA-G levels and disease activity with respect to genotypes. Yoga intervention results in improvement and reduced severity of RA in patients irrespective of the HLA-G 14 bp ins/del or +3142G>C polymorphisms. YBLI may be used as an adjunct therapy in RA independent of the genotypes.

Associations of maternal HLA-G gene polymorphism, perinatal infections and smoking in the family with risk of congenital malformations in the fetus

<h3>ЦЕЛЬ ИССЛЕДОВАНИЯ</h3> Изучить связь материнского полиморфизма гена <i>HLA-G</i> (rs41551813, rs12722477, rs41557518 и rs66554220)<i>,</i> перинатальных инфекций и курения в семье с риском врожденных пороков развития у плода. <h3>МАТЕРИАЛ И МЕТОДЫ</h3> Обследованы 335 женщин, вынашивающих/родивших ребенка с врожденными пороками развития (ВПР), и 418 женщин без ВПР у плода/ребенка. Инфекционный статус беременных женщин оценивали, исходя из данных лабораторных тестов: микроскопического исследования (выявление бактериального вагиноза и вульвовагинального кандидоза, <i>Treponema pallidum</i>); иммуноферментного анализа и полимеразной цепной реакции (ПЦР) (выявление вируса простого герпеса I и II типа, цитомегаловируса и др.; <i>Neisseria gonorrhoeae, Chlamydia trachomatis</i> и др.). Фактор курение в семье оценивали как курение одного или обоих партнеров. Типирование полиморфных сайтов Thr31Ser (rs41551813, <i>HLA-G*01:03</i>) в экзоне 2, Leu110Ile (rs12722477, <i>HLA-G*01:04</i>)<i></i> и <i>1</i>597 delC (rs41557518, <i>HLA-G*01:05N</i>) в экзоне 3 гена <i>HLA-G</i> проводили методом асимметричной ПЦР. Полиморфизм гена <i>HLA-G</i> 14 bp Ins/Del (rs66554220) в 3’UTR области экзона 8 детектировали с помощью электрофоретического разделения продуктов амплификации в 7% полиакриламидном геле. <h3>РЕЗУЛЬТАТЫ</h3> Проведенное исследование показало, что перинатальные инфекции матери (OR=1,75 [1,31—2,34]) и курение в семье (OR=1,75 [1,31—2,34]) являлись основными факторами риска ВПР у плода (<i>P</i>&lt;0,001). Материнская аллель 110Ile <i>HLA-G</i> (rs12722477, <i>HLA-G*01:04</i>) была дополнительным фактором риска ВПР у плода после введения поправки на перинатальные инфекции и курение в семье (OR=1,86 [1,13—3,05], <i>P</i>_c=0,03). Материнские полиморфные сайты rs41551813, rs41557518 и rs66554220 гена <i>HLA-G</i> значимо не влияли на риск ВПР у плода. <h3>ЗАКЛЮЧЕНИЕ</h3> Перинатальные инфекции матери, курение в семье и материнский полиморфизм гена <i>HLA-G</i> rs12722477 могут быть факторами риска врожденных пороков развития у плода. Наши результаты способствуют пониманию молекулярных механизмов формирования патологии в системе «мать — плод».

Association of human leukocyte antigen-G 14-bp insertion/deletion and +3142G&gt;C polymorphisms with rheumatoid arthritis: A meta-analysis

This meta-analysis investigated the significant association between human leukocyte antigen (HLA)-G 14-bp insertion/deletion and +3142G>C polymorphisms with susceptibility to rheumatoid arthritis (RA). This relationship has been scrutinized in several studies, and the findings are controversial. The association studies related to HLA-G gene polymorphisms and RA were extracted from PubMed, Mendeley, ScienceDirect, and Google Scholar databases up to December 31, 2020. Finally, a total of 1516 cases and 1683 control samples were chosen from 7 published research articles for this meta-analysis. A significant association was evaluated using the pooled odds ratios (ORs) and 95% confidence intervals (CIs) under allelic, dominant, recessive, and additive models. Overall, there is absence of significant association between 14-bp ins/del polymorphism and RA (recessive model: OR = 1.012, 95% CI = 0.841–1.217, P = 0.900; dominant model: OR = 1.068, 95% CI = 0.919–1.241, P = 0.393; ins/ins vs. del/del: OR = 1.059, 95% CI = 0.861–1.303, P = 0.587). In the case of +3142G>C polymorphism, the recessive model (OR = 1.332, 95% CI = 1.083–1.640, P = 0.007) showed a significant association with RA susceptibility. When subgroup analysis was done by ethnicity, +3142G>C polymorphism was found to be significantly associated with RA susceptibility in the Asian population under the recessive model (OR = 1.450, 95% CI = 1.048–2.006, P = 0.025). This meta-analysis brings to light that there was no significant association between 14-bp ins/del polymorphism and RA susceptibility. Whereas, +3142G>C polymorphism was found to be significantly associated with susceptibility to RA.

Study of relationships between maternal HLA-G gene polymorphism and intrauterine infection with risk of congenital malformations

This study aims for assessing relationships between maternal HLA-G gene polymorphisms (rs41551813, rs12722477, rs41557518) and intrauterine infection with the risk of congenital malformations (CM) in infants. We studied 331 women who had offspring with CMs, and 408 women with one or more healthy children. Influence of the intrauterine infection was analyzed on the basis of laboratory tests. Diagnostics of bacterial vaginosis and vulvovaginal candidiasis by microscopic examination were conducted. Viral infections (herpes simplex virus type 2, cytomegalovirus, human papilloma virus type 16/18) as well as Neisseria gonorrhoeae, Chlamydia trachomatis, Mycoplasma hominis, Mycoplasma genitalium, Ureaplasma urealyticum, Gardnerella vaginalis; Trichomonas vaginalis and Toxoplasma gondii were detected by enzyme-linked immunoassay or polymerase chain reaction (PCR) techniques. The data were obtained from the medical cards of the surveyed women. The gene polymorphisms were typed for Thr31Ser (rs41551813, HLA-G*01:03) in exon 2, Leu110Ile (rs12722477, HLA-G*01:04) and 1597 delС (rs41557518, HLA-G*01:05N) in exon 3 HLA-G using real-time PCR followed by melting analysis. The study showed that maternal age was not a significant risk factor for CMs in the fetus/newborns. Meanwhile, the maternal intrauterine infections were shown to be a significant risk factor for CMs in their infants (OR = 1.57 (1.08-2.29); p = 0.002). It was found that the 110 Ile allele (HLA-G *01:04) was a risk factor for CMs incidence in the fetus/newborns (OR = 1.57 (1.08-2.29), p = 0.01). No association was found between the maternal rs41551813 and rs41557518 HLA-G genetic polymorphisms and CMs in the infants. Hence, intrauterine infections and maternal 110 Ile allele (HLA-G *01:04) may be suggested as risk factors for birth defects in the children. Our results will be useful in understanding the molecular mechanisms of immune disorders in feto-maternal interface.

Study of relationships between HLA-G gene polymorphism, intrauterine infection and recurrent miscarriage in women

The relationship between the HLA-G gene polymorphism (rs41551813, rs12722477, rs41557518), intrauterine infection and recurrent miscarriage (RM) in women were studied. The case group consisted of 180 patients with RM, defined as two or more consecutive miscarriages (min = 2; max = 8) at up to 20 weeks of gestation, and with clinically confirmed pregnancies and non-viable fetuses. At the time of examination. the women were enrolled from the Genetic Counseling Center at the Kemerovo Regional Clinical Hospital, Kemerovo, Russia, and were not pregnant. Each patient underwent a gynecological examination. We excluded women with a history of medical abortion, birth, and ectopic pregnancies. In addition, we excluded women with endocrine (e.g. diabetes) disorders. To exclude other known causes of spontaneous abortion, the following tests were performed: ultrasound examination of pelvic organs, and karyotyping in women and men. The women’s mean age in the RM group, was 29.6±4.8 (SD) years. The control group comprised 408 fertile women. These women didn’t have a history of spontaneous abortion, or a family history of congenital malformations. They have born, at least, 1-2 healthy children. Women’s mean age at birth of last child was 26.8±5.2 (SD) years. Influence of the intrauterine infection was analyzed on the basis of laboratory tests. Diagnostics of bacterial vaginosis and vulvo-vaginal candidiasis by microscopic examination was conducted. Viral agent infections (herpes simplex virus type 2, cytomegalovirus, human papilloma virus type 16/18), Chlamydia trachomatis, Mycoplasma hominis, Ureaplasma urealyticum, Gardnerella vaginalis and Trichomonas vaginalis were detected by enzyme-linked immunoassay and polymerase chain reaction (PCR). The data were obtained from the medical cards of the surveyed women. All the women gave a written informed consent before participating in the study. Typing of polymorphisms of Thr31Ser (rs41551813, HLA-G*01:03) in exon 2, Leu110Ile (rs12722477, HLA-G*01:04) and 1597 delС (rs41557518, HLA-G*01:05N) in exon 3 HLA-G genes were performed by realtime PCR followed by melting analysis. The study showed that the intrauterine infection was not a risk factor for RM (p = 0.30) in the examined women. It was found that the 110 Ile allele (HLA-G *01:04) was a risk factor for RM both in women with intrauterine infection [ORa = 4.50 (2.41-8.38), p = 2.09e-06], and in women without infection [ORa = 2.46 (1.44-4.21), p = 0.0009]. The cooperative influence of genetic and infections factors with the risk of RM in women was revealed [ORa+f = 3.50 (2.01-6.09), p = 8.78e-06]. Our results will be useful in understanding the molecular mechanisms of immune disorders in fetomaternal interface, and for choosing the strategy of management and treatment in women with RM.

Genetic polymorphism of HLA-G gene (G*01:03, G*01:04, and G*01:05N) in Iraqi patients with inflammatory bowel disease (ulcerative colitis and Crohn\u2019s disease)

BackgroundHuman leukocyte antigen-G (HLA-G) has been proposed to influence susceptibility to inflammatory bowel disease (IBD). Therefore, the genetic association between HLA-G alleles and two clinical phenotypes of IBD (ulcerative colitis [UC] and Crohn’s disease [CD]) was evaluated in Iraqi patients. A case-control study was performed on 50 UC and 50 CD patients and 100 healthy controls (HC). Three HLA-G alleles (G*01:03, G*01:04, and G*01:05N) were determined using sequence-specific polymerase chain reaction assay followed by product digestion with restriction endonucleases (Hinf-I, BseR-I, and PpuM-I, respectively).ResultsThe G*01:03 allele was not detected in IBD patients (UC and CD) or HC, while G*01:04 and G*01:05N alleles showed polymorphic frequencies. The allele G*01:04 was significantly associated with susceptibility to UC (odds ratio [OR] = 2.55; 95% confidence interval [CI] = 1.27–5.13; corrected probability [pc] = 0.018) and CD (OR = 4.45; 95% CI = 2.11–9.41; pc < 0.001). The allele G*01:05N was also associated with increased risk of UC (OR = 4.17; 95% CI = 1.32–13.21; pc = 0.032) and CD (OR = 4.75; 95% CI = 1.53–14.78; pc = 0.014). These associations were more pronounced in IBD (UC + CD), and a significantly increased risk for IBD was found with the alleles G*01:04 (OR = 3.32; 95% CI = 1.86–5.95; pc < 0.001) and G*01:05N (OR = 4.46; 95% CI = 1.59–12.47; pc = 0.008). A stratification of IBD patients according to some demographic and clinical characteristics revealed that frequencies of both alleles showed no significant differences between the subgroups of patients in each stratum. Soluble HLA-G was not influenced by HLA-G alleles in patients or HC. UC was an exception, and the presence of G*01:04 allele was associated with a significantly higher mean of soluble HLA-G compared to patients without the allele (189.6 ± 24.0 vs. 168.6 ± 27.2 ng/mL; p = 0.033).ConclusionThis study indicated that HLA-G*01:04 and HLA-G*01:05N alleles may influence susceptibility to UC and CD in Iraqi patients.

Human leucocyte antigen – G gene polymorphism in laryngeal squamous cell carcinoma patients in Mansoura University Hospitals

ABSTRACT This study aimed to detect the genetic association of HLA-G gene polymorphism with LSCC. It was a comparative study estimating the prevalence of both HLA-G 14-bp insertion versus deletion polymorphism and HLA-G*01:05 N null allele using PCR-RFLP. HLA-G 14-bp deletion allele was highly recorded in patients with LSCC (63.0%) whereas insertion allele (37.0%) was lower. The −14/-14 and −14/+14 genotypes were significantly higher in LSCC cases whereas +14/+14 genotype was not. HLA-G*01:05 N null allele was found in 39 LSCC cases (43.8%) and 47 control (52.8%), (p = 0.23). Distribution of studied alleles and genotypes showed no significant correlation to the clinic-pathological features of included cases. There was a significant association between HLA-G 14-bp deletion allele (versus insertion allele) and the risk of LSCC but no clear association between null allele and occurrence of LSCC was detected.

Analysis of HLA-G long-read genomic sequences in mother\u2013offspring pairs with preeclampsia

Preeclampsia is a pregnancy-induced disorder that is characterized by hypertension and is a leading cause of perinatal and maternal–fetal morbidity and mortality. HLA-G is thought to play important roles in maternal–fetal immune tolerance, and the associations between HLA-G gene polymorphisms and the onset of pregnancy-related diseases have been explored extensively. Because contiguous genomic sequencing is difficult, the association between the HLA-G genotype and preeclampsia onset is controversial. In this study, genomic sequences of the HLA-G region (5.2 kb) from 31 pairs of mother–offspring genomic DNA samples (18 pairs from normal pregnancies/births and 13 from preeclampsia births) were obtained by single-molecule real-time sequencing using the PacBio RS II platform. The HLA-G alleles identified in our cohort matched seven known HLA-G alleles, but we also identified two new HLA-G alleles at the fourth-field resolution and compared them with nucleotide sequences from a public database that consisted of coding sequences that cover the 3.1-kb HLA-G gene span. Intriguingly, a potential association between preeclampsia onset and the poly T stretch within the downstream region of the HLA-G*01:01:01:01 allele was found. Our study suggests that long-read sequencing of HLA-G will provide clues for characterizing HLA-G variants that are involved in the pathophysiology of preeclampsia.

Implication of Soluble HLA-G and HLA-G +3142G/C Polymorphism in Breast Cancer Patients Receiving Adjuvant Therapy in Tanzania.

Background:During cancer growth, immunosuppressive microenvironment is created that enables tumour cells to evade an eliminative immune response and hence manage to grow into malignancy. HLA-G, existing as either membrane-bound (mHLA-G) or soluble (sHLA-G) molecule is thought to be immunosuppressive and produced more by tumor cells. The +3142G/C polymorphism in HLA-G gene affects its expression, and G allele is considered to be a protective mutant allele associated with less expression of HLA-G. The implication of HLA-G in cancer development has been reported in different cancers and populations. But, its implication in most African populations has not yet been investigated. The aim of this study was to determine the possible associations of soluble HLA-G and HLA-G +3142G/C SNP with breast cancer. Materials and Methods:75 breast cancer patients and 84 normal controls were recruited in this study. The genotyping of HLA-G +3142G/C polymorphism was determined by LightSNiP typing assay using quantitative Real-Time PCR and sHLA-G levels were determined by ELISA. Results:The sHLA-G levels were significantly lower in breast cancer patients than in controls (p<0.001). Also, they were significantly lower in mastectomized patients compared to non-mastectomized patients (p=0.018). The ROC analysis revealed a significant ability of sHLA-G to differentiate breast cancer patients versus normal controls (AUC=0.697, 95% CI= 0.619-0.767, p<0.001) and identify mastectomized patients (AUC=0.667, 95% CI= 0.549 to 0.772, p=0.041). The assessment of +3142G/C polymorphism revealed a relatively similar distribution of frequencies of genotypes and alleles between breast cancer patients and normal controls (p>0.05) and was neither associated with sHLA-G levels. Conclusion:While the +3142G/C SNP was found not to be relevant to breast cancer, the changes of sHLA-G levels in response to medical interventions such as mastectomy may be translated into its potential prognostic utility for breast cancer. More studies are needed to provide clear evidence of sHLA-G as a diagnostic and prognostic marker of breast cancer in Tanzania.