Allelic variability in the adaptive immune receptor loci, which harbor the gene segments that encode B cell and T cell receptors (BCR/TCR), is of critical importance for immune responses to pathogens and vaccines. Adaptive immune receptor repertoire sequencing (AIRR-seq) has become widespread in immunology research making it the most readily available source of information about allelic diversity in immunoglobulin (IG) and T cell receptor (TR) loci. Here, we present a novel algorithm for extrasensitive and specific variable (V) and joining (J) gene allele inference, allowing the reconstruction of individual high-quality gene segment libraries. The approach can be applied for inferring allelic variants from peripheral blood lymphocyte BCR and TCR repertoire sequencing data, including hypermutated isotype-switched BCR sequences, thus allowing high-throughput novel allele discovery from a wide variety of existing data sets. The developed algorithm is a part of the MiXCR software. We demonstrate the accuracy of this approach using AIRR-seq paired with long-read genomic sequencing data, comparing it to a widely used algorithm, TIgGER. We applied the algorithm to a large set of IG heavy chain (IGH) AIRR-seq data from 450 donors of ancestrally diverse population groups, and to the largest reported full-length TCR alpha and beta chain (TRA and TRB) AIRR-seq data set, representing 134 individuals. This allowed us to assess the genetic diversity within the IGH, TRA, and TRB loci in different populations and to establish a database of alleles of V and J genes inferred from AIRR-seq data and their population frequencies with free public access through VDJ.online database.
- MeSH
- alely * MeSH
- algoritmy * MeSH
- genetická variace MeSH
- lidé MeSH
- receptory antigenů B-buněk genetika imunologie MeSH
- receptory antigenů T-buněk genetika imunologie MeSH
- sekvenční analýza DNA metody MeSH
- software * MeSH
- vysoce účinné nukleotidové sekvenování metody MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Genetic variations in a common single nucleotide polymorphism in the ninth intron of the KIBRA gene have been linked to memory performance and risk of Alzheimer's disease (AD). OBJECTIVE: We examined the risk of AD related to presence of KIBRA T allele (versus CC homozygote) and to memory performance. The role of established genetic risk factors APOE ε4 and BDNF Met was also considered. METHODS: Participants were cognitively healthy individuals (n = 19), participants with amnestic mild cognitive impairment (aMCI) due to AD (n = 99) and AD dementia (n = 37) from the Czech Brain Aging Study. Binary and multinomial logistic regressions compared odds of belonging to a certain diagnostic category and multivariate linear regressions assessed associations with memory. RESULTS: KIBRA T allele was associated with increased AD dementia risk (odds ratio [OR] = 5.98, p = 0.012) compared to KIBRA CC genotype. In APOE ε4 negative individuals, KIBRA T allele was associated with a greater risk of both aMCI due to AD (OR = 6.68, p = 0.038) and AD dementia (OR = 15.75, p = 0.009). In BDNF Met positive individuals, the KIBRA T allele was associated with a greater risk of AD dementia (OR = 10.98, p = 0.050). In AD dementia, the association between KIBRA T allele and better memory performance approached significance (β = 0.42; p = 0.062). The link between possessing the KIBRA T allele and better memory reached statistical significance only among BDNF Met carriers (β = 1.21, p = 0.027). CONCLUSIONS: Findings suggest that KIBRA T allele may not fully protect against AD dementia but could potentially delay progression of post-diagnosis cognitive deficits.
- MeSH
- alely MeSH
- Alzheimerova nemoc * genetika MeSH
- apolipoprotein E4 genetika MeSH
- genetická predispozice k nemoci genetika MeSH
- genotyp MeSH
- intracelulární signální peptidy a proteiny genetika MeSH
- jednonukleotidový polymorfismus * genetika MeSH
- kognitivní dysfunkce * genetika MeSH
- lidé MeSH
- mozkový neurotrofický faktor genetika MeSH
- neuropsychologické testy MeSH
- paměť fyziologie MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Fuchs endothelial corneal dystrophy (FECD) is the most common repeat-mediated disease in humans. It exclusively affects corneal endothelial cells (CECs), with ≤81% of cases associated with an intronic TCF4 triplet repeat (CTG18.1). Here, we utilise optical genome mapping (OGM) to investigate CTG18.1 tissue-specific instability to gain mechanistic insights. METHODS: We applied OGM to a diverse range of genomic DNAs (gDNAs) from patients with FECD and controls (n = 43); CECs, leukocytes and fibroblasts. A bioinformatics pipeline was developed to robustly interrogate CTG18.1-spanning DNA molecules. All results were compared with conventional polymerase chain reaction-based fragment analysis. FINDINGS: Analysis of bio-samples revealed that expanded CTG18.1 alleles behave dynamically, regardless of cell-type origin. However, clusters of CTG18.1 molecules, encompassing ∼1800-11,900 repeats, were exclusively detected in diseased CECs from expansion-positive cases. Additionally, both progenitor allele size and age were found to influence the level of leukocyte-specific CTG18.1 instability. INTERPRETATION: OGM is a powerful tool for analysing somatic instability of repeat loci and reveals here the extreme levels of CTG18.1 instability occurring within diseased CECs underpinning FECD pathophysiology, opening up new therapeutic avenues for FECD. Furthermore, these findings highlight the broader translational utility of FECD as a model for developing therapeutic strategies for rarer diseases similarly attributed to somatically unstable repeats. FUNDING: UK Research and Innovation, Moorfields Eye Charity, Fight for Sight, Medical Research Council, NIHR BRC at Moorfields Eye Hospital and UCL Institute of Ophthalmology, Grantová Agentura České Republiky, Univerzita Karlova v Praze, the National Brain Appeal's Innovation Fund and Rosetrees Trust.
- MeSH
- alely MeSH
- expanze trinukleotidových repetic MeSH
- Fuchsova endoteliální dystrofie * genetika patologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- mapování chromozomů MeSH
- nestabilita genomu MeSH
- orgánová specificita genetika MeSH
- senioři MeSH
- transkripční faktor 4 * genetika metabolismus MeSH
- trinukleotidové repetice genetika MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
OBJECTIVES: COVID-19 caused a global pandemic with millions of deaths. Fat mass and obesity-associated gene (FTO) (alias m6A RNA demethylase) and its functional rs17817449 polymorphism are candidates to influence COVID-19-associated mortality since methylation status of viral nucleic acids is an important factor influencing viral viability. METHODS: We tested a population-based cohort of 5233 subjects (aged 63-87 years in 2020) where 70 persons died from COVID-19 and 394 from other causes during the pandemic period. RESULTS: The frequency of GG homozygotes was higher among those who died from COVID-19 (34%) than among survivors (19%) or deaths from other causes (20%), P <0.005. After multiple adjustments, GG homozygotes had a higher risk of death from COVID-19 with odds ratio = 2.01 (95% confidence interval; 1.19-3.41, P <0.01) compared with carriers of at least one T allele. The FTO polymorphism was not associated with mortality from other causes. CONCLUSIONS: Our results suggest that FTO variability is a significant predictor of COVID-19-associated mortality in Caucasians.
- MeSH
- alely MeSH
- COVID-19 * mortalita genetika virologie MeSH
- gen pro FTO * genetika MeSH
- genetická predispozice k nemoci MeSH
- jednonukleotidový polymorfismus * MeSH
- kohortové studie MeSH
- lidé středního věku MeSH
- lidé MeSH
- SARS-CoV-2 fyziologie MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Syphilis is a multistage sexually transmitted disease caused by Treponema pallidum ssp. pallidum. In the Czech Republic, there are around 700-800 new syphilis cases annually, continuously increasing since 2012. This study analyzed a total of 1228 samples from 2004 to 2022. Of the PCR-positive typeable samples (n = 415), 68.7% were fully-typed (FT), and 31.3% were partially-typed. Most of the identified isolates belonged to the SS14-clade and only 6.3% were the Nichols-like cluster. While in the beginning of sample collection isolates have been macrolide-susceptible, recent isolates are completely resistant to macrolides. Among the FT samples, 34 different allelic profiles (APs) were found. Most of the profiles (n = 27) appeared just once in the Czech population, while seven profiles were detected more than twice. The most frequent APs belonged to two separate groups of SS14-like isolates, including group of 1.3.1 (ST 1) and 1.26.1 (ST 25) profiles, and the second group containing 1.1.8 (ST 3), 1.1.1 (ST 2), and 1.1.3 (ST 11) (representing 57.5%, and 25.3% of all detected APs, respectively). Both groups consistently differed in 6 nucleotide positions in five genes (TP0150, TP0324, TP0515, TP0548, and TP0691) coding amino-acid replacements suggesting that one or more of these differences could be involved in the higher success of the first group.
- MeSH
- alely * MeSH
- dospělí MeSH
- genotyp MeSH
- lidé středního věku MeSH
- lidé MeSH
- makrolidy farmakologie MeSH
- multilokusová sekvenční typizace * MeSH
- syfilis * mikrobiologie epidemiologie genetika MeSH
- Treponema pallidum * genetika izolace a purifikace MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
A comprehensive knowledge of human leukocyte antigen (HLA) molecular variation worldwide is essential in human population genetics research and disease association studies and is also indispensable for clinical applications such as allogeneic hematopoietic cell transplantation, where ensuring HLA compatibility between donors and recipients is paramount. Enormous progress has been made in this field thanks to several decades of HLA population studies allowing the development of helpful databases and bioinformatics tools. However, it is still difficult to appraise the global HLA population diversity in a synthetic way. We thus introduce here a novel approach, based on approximately 2000 data sets, to assess this complexity by providing a fundamental synopsis of the most frequent HLA alleles observed in different regions of the world. This new knowledge will be useful not only as a fundamental reference for basic research, but also as an efficient guide for clinicians working in the field of transplantation.
- MeSH
- alely * MeSH
- frekvence genu MeSH
- HLA antigeny * genetika imunologie MeSH
- lidé MeSH
- transplantace hematopoetických kmenových buněk * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Correlated regions of systemic interindividual variation (CoRSIV) represent a small proportion of the human genome showing DNA methylation patterns that are the same in all human tissues, are different among individuals, and are partially regulated by genetic variants in cis. In this study we aimed at investigating single-nucleotide polymorphisms (SNPs) within CoRSIVs and their involvement with pancreatic ductal adenocarcinoma (PDAC) risk. We analyzed 29,099 CoRSIV-SNPs and 133,615 CoRSIV-mQTLs in 14,394 cases and 247,022 controls of European and Asian descent. We observed that the A allele of the rs2976395 SNP was associated with increased PDAC risk in Europeans (p = 2.81 × 10-5). This SNP lies in the prostate stem cell antigen gene and is in perfect linkage disequilibrium with a variant (rs2294008) that has been reported to be associated with risk of many other cancer types. The A allele is associated with the DNA methylation level of the gene according to the PanCan-meQTL database and with overexpression according to QTLbase. The expression of the gene has been observed to be deregulated in many tumors of the gastrointestinal tract including pancreatic cancer; however, functional studies are needed to elucidate the function relevance of the association.
- MeSH
- alely MeSH
- antigeny nádorové * genetika MeSH
- Asijci genetika MeSH
- běloši genetika MeSH
- duktální karcinom slinivky břišní * genetika MeSH
- genetická predispozice k nemoci * MeSH
- GPI-vázané proteiny * genetika MeSH
- jednonukleotidový polymorfismus * MeSH
- lidé středního věku MeSH
- lidé MeSH
- lokus kvantitativního znaku MeSH
- metylace DNA * MeSH
- nádorové proteiny * genetika MeSH
- nádory slinivky břišní * genetika MeSH
- studie případů a kontrol MeSH
- vazebná nerovnováha * MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Background: Thalassemia` is an autosomal recessive hereditary chronic hemolytic anaemia caused by a partial or total deficit in the production of β -globin chains that make up the main adult haemoglobin. Patients with the beta-thalassemia major have changes in thyroid function and result from thyroid function tests. The B-cell lymphoma /leukemia11A (BCL11A) gene is mainly located in the human chromosome 2p16.1 region; the BCL11A gene can regulate the expression of fetal haemoglobin.The aim: analysis of the association between beta-thalassemia and the BCL11A gene polymorphism in the Iraqi patient and to evaluate the effect of beta-thalassemia on the thyroid gland through the determination of free thyroxine concentration.Method: There were 150 participants in this study, split into two primary groups beta-thalassemia patients and healthy individuals. The result is measured using the ELISA for measurement of free thyroxine and polymerase chain reaction techniques for amplification of B-cell lymphoma /leukemia11A (BCL11A) gene polymorphism.Results: The findings showed a substantial drop in free thyroxine levels in beta-thalassemia patient groups as compared to the control group (P 0.01). The BCL11A gene has three alleles: homozygous CC, heterozygous TC, and homozygous TT. At (431 bais pair and 280 bais pair), (431 bais pair, 280 bais pair, and 195 bais pair), and (431 bais pair, and 195 bais pair), the bands appeared, respectively. The BCL11A rs11886868 gene is affected overall, and research into the causes of thalassemia found a substantial correlation between the BCL11A (rs 11886868) T and C-alleles and thalassemia (P-value = 0.004). The fact that these people have low serum thyroxine (T4) levels highlights the importance of routine screening to assess their endocrine function.
- MeSH
- alely MeSH
- beta-talasemie * genetika krev MeSH
- elektroforéza MeSH
- ELISA metody MeSH
- lidé MeSH
- polymorfismus genetický MeSH
- protoonkogeny MeSH
- štítná žláza patofyziologie MeSH
- thyroxin * krev MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- klinická studie MeSH
BACKGROUND: Cystic fibrosis (CF) is a rare multi-systemic recessive disorder. The spectrum and the frequencies of CFTR mutations causing CF vary amongst different populations in Europe and the Middle East. In this study, we characterised the distribution of CF-causing mutations (i.e. pathogenic variants in the CFTR gene) in a representative CF cohort from the Kingdom of Bahrain based on a three-decade-long analysis at a single tertiary centre. We aim to improve CF genetic diagnostics, introduce of CF neonatal screening and provide CFTR modulator therapy (CFTRm). METHODS: CFTR genotyping and associated clinical information were drawn from a longitudinal cohort. We sequenced 56 people with CF (pwCF) that had one or both CFTR mutations unidentified and carried out comprehensive bioinformatic- and family-based segregation analyses of detected variants, including genotype-phenotype correlations and disease incidence estimates. The study methodology could serve as a basis for other non-European CF populations with a high degree of consanguinity. RESULTS: Altogether 18 CF-causing mutations were identified, 15 of which were not previously detected in Bahrain, accounting for close to 100% of all population-specific alleles. The most common alleles comprise c.1911delG [2043delG; 22.8%], c.2988+1G > A [3120+1G>A; 16.3%], c.2989-1G>A [3121-1G>A; 14.1%], c.3909C>G [N1303K; 13.0%], and c.1521_1523delCTT [p.PheF508del; 7.6%]. Although the proportion of 1st cousin marriages has decreased to 50%, the frequency of homozygosity in our pwCF is 67.4%, thereby indicating that CF still occurs in large, often related, families. pwCF in Bahrain present with faltering growth, pancreatic insufficiency and classical sino-pulmonary manifestations. Interestingly, two pwCF also suffer from sickle cell disease. The estimated incidence of CF in Bahrain based on data from the last three decades is 1 in 9,880 live births. CONCLUSION: The most commonCF-causing mutations in Bahraini pwCF were identified, enabling more precise diagnosis, introduction of two-tier neonatal screening and fostering administration of CFTRm.
- MeSH
- alely MeSH
- cystická fibróza * genetika MeSH
- dítě MeSH
- dospělí MeSH
- genetické asociační studie metody MeSH
- genotyp MeSH
- kohortové studie MeSH
- kojenec MeSH
- lidé MeSH
- mladiství MeSH
- mutace * MeSH
- novorozenec MeSH
- novorozenecký screening MeSH
- předškolní dítě MeSH
- protein CFTR * genetika MeSH
- Check Tag
- dítě MeSH
- dospělí MeSH
- kojenec MeSH
- lidé MeSH
- mladiství MeSH
- mužské pohlaví MeSH
- novorozenec MeSH
- předškolní dítě MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Bahrajn MeSH
The immunogenome is the part of the genome that underlies immune mechanisms and evolves under various selective pressures. Two complex regions of the immunogenome, major histocompatibility complex (MHC) and natural killer cell receptor (NKR) genes, play an important role in the response to selective pressures of pathogens. Their importance is expressed by their genetic polymorphism at the molecular level, and their diversity associated with different types of diseases at the population level. Findings of associations between specific combinations of MHC/NKR haplotypes with different diseases in model species suggest that these gene complexes did not evolve independently. No such associations have been described in horses so far. The aim of the study was to detect associations between MHC and NKR gene/microsatellite haplotypes in three horse breed groups (Camargue, African, and Romanian) by statistical methods; chi-square test, Fisher's exact test, Pearson's goodness-of-fit test and logistic regression. Associations were detected for both MHC/NKR genes and microsatellites; the most significant associations were found between the most variable KLRA3 gene and the EQCA-1 or EQCA-2 genes. This finding supports the assumption that the KLRA3 is an important receptor for MHC I and that interactions of these molecules play important roles in the horse immunity and reproduction. Despite some limitations of the study such as low numbers of horses or lack of knowledge of the selected genes functions, the results were consistent across different statistical methods and remained significant even after overconservative Bonferroni corrections. We therefore consider them biologically plausible.
