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Investigations of the Genetic aspects of the mixed Lymphocyte culture reaction in Southern Africadu Toit, Ernette D 16 April 2020 (has links)
The genetic relationship between the serologically detectable antigens of the HLA-A and B loci and the mixed
lymphocyte culture (MLC) reaction is of utmost importance in the understanding of histocompatibility. From the literature it appeared that neither the HLA-A, B genotype nor the MLC reaction is the complete answer to donorrecipient selection in organ transplantation. This study was therefore initiated in June 1971 in an attempt to clarify the problem. It is inherent in a project of this nature that much time is spent in collecting samples from donors in diverse areas. Most experiments had to be repeated two or three times, therefore some of the problems we set out to resolve were clarified by other workers before we were able to complete our investigations.
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The differential induction of HLA class I by interferon-#alpha#Isamat, Marcos January 1992 (has links)
No description available.
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Abnormal expression of immunoractive molecules in urological tumours and their possible relevance in escape from immunological surveillanceHussain, Rafat Fakhir January 1995 (has links)
No description available.
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Exploration of methods for sequence based HLA typing and application to patients with hair dye allergyGarcia-Batres, Carlos R. Unknown Date
No description available.
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The role of the major histocompatibility complex and the Leukocyte receptor complex genes in susceptibility to tuberculosis in a South African populationSalie, Muneeb 04 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Tuberculosis (TB) disease results in approximately 2 million deaths annually and is the
leading cause of death due to a single infectious agent. Previous studies have indicated that
host genetics play an important role in the development of TB. This together with pathogen
and environmental factors intensifies the complexity of this disease.
The Major Histocompatibility Complex (MHC) and Leukocyte Receptor Complex (LRC)
comprise several genes which are known to be important modulators of the host immune
response. The human leukocyte antigen (HLA) class-I genes of the MHC are involved in the
presentation of pathogenic antigens on the surfaces of infected cells, while the killer cell
immunoglobulin-like receptors (KIRs) of the LRC are involved in the recognition of self and
non-self cells. Natural Killer (NK) cells through their KIRs are thus able to kill non-self cells
through recognition of the class-I molecules expressed. Additionally, HLAs and KIRs are
extremely polymorphic and differ markedly across populations of different ethnicities.
Here we studied these genes and their polymorphisms in the South African Coloured (SAC)
population to determine their involvement in susceptibility to TB, susceptibility to disease
caused by specific Mycobacterium tuberculosis subtypes, and understanding their ancestral
contribution to the SAC with regards to the development of TB.
We showed that the KIR3DS1 gene and KIR genotypes with five or more activating KIRs,
and the presence of 3DS1, protected against the development of active TB in the SAC
population. Several HLA class-I alleles were identified as susceptibility factors for TB
disease. With regards to genes of the MHC and LRC, several loci were found to alter
susceptibility to TB in the SAC population, including MDC1, BTNL2, HLA-DOA, HLA-DOB,
C6orf10, TAP2, LILRA5, NCR1, NLRP7 and the intergenic regions between HLA-C/WASF5P
and LAIR1/TTYH1. We showed that the Beijing strain occurred more frequently in individuals with multiple
disease episodes, with the HLA-B27 allele lowering the odds of having an additional episode.
Associations were identified for specific HLA types and disease caused by the Beijing, Latin
America-Mediterranean (LAM), Low-Copy Clade (LCC), and Quebec strains. HLA types
were associated with disease caused by strains from the Euro-American or East Asian
lineages, and the frequencies of these alleles in their sympatric human populations identified
potential co-evolutionary events between host and pathogen.
Finally, we showed that the SAC population is the most diverse SA population with regards
to HLA alleles and KIR genotypes, as would be expected given the admixture of the SAC.
Based on the HLA allele class-I profiles across SA populations, we noted that the Ag85BESAT-
6, Ag85B-TB10.4 and Mtb72f vaccines currently undergoing clinical trials would
have low efficacy across most SA populations. We showed that the MHC and LRC regions in
SAC healthy controls are predominantly of European ancestry, and that SAC TB cases are
more closely related to Khoisan and black SA population groups.
Our work highlights the importance of investigating both host and pathogen genetics when
studying TB disease development and that understanding the genetic ancestral contributions
to the SAC population can contribute to the identification of true and novel TB causing
variants. / AFRIKAANSE OPSOMMING: Tuberkulose (TB) is jaarliks verantwoordelik vir ongeveer 2 miljoen sterftes en is die
hoofoorsaak van dood as gevolg van „n aansteeklike siekte. Vorige navorsingstudies het
aangedui dat die genetiese samestelling van die gasheer „n beduidende rol speel in die
ontwikkeling van TB. Die kompleksiteit van hierdie siekte word vererger deur die
betrokkenheid van die gasheer genoom sowel as bakteriële en omgewings faktore.
Die Major Histocompatibility Complex (MHC) en Leukocyte Receptor Complex (LRC)
bestaan uit verskeie gene wat die gasheer immuunrespons verstel. Die human leukocyte
antigen (HLA) klas I gene van die MHC is betrokke by die aanbieding van patogeniese
antigene op die oppervlak van geïnfekteerde selle, terwyl die killer cell immunoglobulin-like
receptors (KIRs), geleë in die LRC, betrokke is by die herkenning van eie en vreemde selle.
NK selle, deur middel van hul KIRs, kan dus vreemde selle uitwis aangesien hulle die
uitgedrukte klas I molekules kan herken. Beide HLA en KIRs is hoogs polimorfies en verskil
beduidend tussen etniese groepe.
In hierdie studie is die bogenoemde gene en hul polimorfismes in die Suid Afrikaanse
Kleurling bevolking (SAC) ondersoek om vas te stel tot watter mate dit genetiese vatbaarheid
vir TB, asook vatbaarheid vir TB wat deur spesifieke Mycobacterium tuberculosis subtipes
veroorsaak word, beïnvloed. Daar is ook gepoog om te verstaan hoe die voorouerlike bydrae
van hierdie gene die SAC met betrekking tot TB vatbaarheid affekteer.
Die resultate van die studie het aangedui dat die KIR3DS1 geen en KIR genotipes met vyf of
meer aktiewe KIRs en die teenwoordigheid van 3DS1, die SAC bevolking beskerm teen die
ontwikkeling van aktiewe TB. Verskeie HLA klas I allele is geïdentifiseer as
vatbaarheidsfaktore vir TB. Talle lokusse van die MHC en LRC gene is ook as
vatbaarheidsfaktore vir TB in die SAC bevolking geïdentifiseer, insluitende MDC1, BTNL2, HLA-DOA, HLA-DOB, C6orf10, TAP2, LILRA5, NCR1, NLRP7 en die intergeniese areas
tussen HLA-C/WASF5P en LAIR1/TTYH1.
Die studie het aangedui dat die Beijing stam meer voorkom in individue wat verskeie kere
TB gehad het en dat die HLA-B27 alleel die kanse om „n verdere episode te hê, verlaag het.
Assosiasies is geïdentifiseer tussen spesifieke HLA tipes en siekte veroorsaak deur die
Beijing, LAM, LCC, en Quebec TB stamme. HLA tipes was geassosieer met siekte
veroorsaak deur TB stamme van Euro-Amerikaanse en Oos-Asiëse afkoms. Die frekwensies
van hierdie allele, in hul ooreenstemmende mensbevolkings, dui op „n potensïele koevolusionêre
gebeurtenis tussen die gasheer en patogeen.
Die studie het ook vasgestel dat die SAC populasie die mees diverse SA bevolking is met
betrekking tot die HLA allele en KIR genotipes, soos verwag sou word gegewe die gemengde
genetiese herkoms van die SAC. Gebaseer op die HLA allele klas I profiel van verskillende
SA bevolkings merk ons op dat die Ag85B-ESAT-6, Ag85B-TB10.4 en Mtb72f vaksiene,
wat huidiglik kliniese toetsing ondergaan, nie so effektief in die meeste SA bevolkings sal
wees nie. Die studie het ook bewys dat die MHC en LRC streke in gesonde SAC kontroles,
grootliks afkomstig was van „n Europese nalatenskap en dat die SAC TB gevalle meer
verwant is aan die Khoisan en swart SA bevolkings.
Hierdie studie beklemtoon die noodsaaklikheid om beide gasheer en patogeen genetika te
bestudeer wanneer die ontwikkeling van TB ondersoek word en dat die verstaan van die
genetiese voorouerlike bydrae van die SAC bevolking kan bydra tot die identifisering van
ware en nuwe TB-veroorsakende variante.
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Frequência do HLA classe I e II na pneumopatia intersticial e na hipertensão arterial pulmonar em pacientes com esclerose sistêmica / Class I and II HLA frequency in interstitial lung disease and pulmonary arterial hypertension in patients with systemic sclerosisDel Rio, Ana Paula Toledo, 1980- 21 August 2018 (has links)
Orientador: Manoel Barros Bertolo / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-21T17:57:00Z (GMT). No. of bitstreams: 1
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Previous issue date: 2012 / Resumo: Introdução: A esclerose sistêmica (ES) é uma doença autoimune caracterizada por disfunção endotelial, vasculopatia obliterativa, fibrose cutânea e visceral. Trata-se de doença poligênica complexa que se manifesta em indivíduos geneticamente predispostos com exposição a fator ambiental ou outro precipitante e seu desenvolvimento depende da interação entre processos imunológicos, vasculares e fibróticos. Estudos genéticos prévios procuram correlacionar os alelos HLA classe I e II e as manifestações clínicas da doença. A fibrose pulmonar (FP) e a hipertensão arterial pulmonar (HAP) são, atualmente, os acometimentos com maior impacto prognóstico e as principais causas de óbito nos pacientes com ES. A expressão do autoanticorpo antitopoisomerase I (anti-Scl70) é um forte preditor de FP, associada à forma difusa e a HAP está relacionada ao anticorpo anticentrômero e à forma limitada da doença. Objetivos: O objetivo deste estudo foi avaliar a participação do HLA na expressão da doença e suas manifestações clínicas de pior prognóstico (FP e HAP) em pacientes com ES em uma população miscigenada. Métodos: Foram incluídos os pacientes com ES seguidos no ambulatório de Reumatologia da Universidade Estadual de Campinas (UNICAMP) de 2008 a 2011. Os dados clínicos foram obtidos através da análise dos prontuários. A genotipagem dos alelos Classe I e II foi realizada através da técnica de amplificação pela reação em cadeia da polimerase, utilizando seqüências específicas de primers. A análise estatística incluiu o teste exato de Fisher e o teste do qui-quadrado de Pearson. Foram considerados significativos valores de p ? 0,05. A razão de prevalência foi estimada pelo método delta. Resultados Cento e quarenta e um pacientes (120 mulheres e 21 homens) foram estudados, sendo 33,3% ES difusa, 62,4% ES limitada e 4,3% ES sine scleroderma. A FP foi considerada em 61 pacientes (43,3%), os alelos HLA-A*30 e DQB1*04 foram relacionados à suscetibilidade. No entanto, os alelos HLA-DRB1*01 e DQB1*05 foram relacionados à ausência desta manifestação. A HAP foi diagnosticada em 19 pacientes (13,5%) e teve associação com HLA-B*35 e C*04, enquanto o alelo C*03 pareceu ser protetor. Conclusões: Este estudo aponta para associação de alguns alelos do HLA classe I e II às manifestações clínicas de maior morbimortalidade na ES nesta série de casos. Estes achados não foram semelhantes aos encontrados previamente em outras populações, o que evidencia múltiplos padrões genéticos na ES / Abstract: Introduction: Systemic sclerosis (SSc) is an autoimmune disease characterized by endothelial dysfunction, occlusive vasculopathy, cutaneous and visceral fibrosis. This is a complex polygenic disease that manifests in genetically predisposed individuals with environmental or other precipitating factor exposure and its development depends on the interaction between immunological, vascular and fibrotic processes. Previous genetic studies aimed to correlate class I and II HLA and the clinical manifestations of the disease. Pulmonary fibrosis (PF) and pulmonary arterial hypertension (PAH) are currently the worse prognostic features and the main causes of death in patients with SSc. The presence of anti-topoisomerase I antibody (anti-Scl70) is a strong predictor of FP, associated with diffuse SSc and PAH is related to anticentromere and the limited form of the disease. Objectives: The aim of this study was to evaluate the HLA involvement in disease expression and poor prognostic clinical features, pulmonary fibrosis (PF) and pulmonary arterial hypertension (PAH), in patients diagnosed with systemic sclerosis (SSc) in a multiethnic population. Methods: SSc patients followed 2008-2011 were included and clinical data were obtained through records review. Molecular HLA typing was performed (PCR amplification technique using sequence of specific primers). Statistical analysis included Fisher's exact test and Pearson's corrected chi-square test. P values ? 0.05 were considered significant. The prevalence ratio was estimated by delta method. Results: One hundred forty-one patients (120 women and 21 men) were studied, 33,3% dcSSc, 62,4% lcSSc and 4,3% sine scleroderma. PF was present in 61 patients (43,3%), HLA-A*30 and DQB1*04 were related to susceptibility. However, HLA-DRB1*01 and DQB1*05 alleles were protective. PAH was diagnosed in 19 (13,5%) and had association with HLA-B*35 and C*04, whereas C*03 seemed to be protective. Conclusions: Our current study documents the association of some class I and II HLA alleles with the most severe clinical manifestations in a multiethnic case series. Our findings were not absolutely similar to the previous data in other populations / Mestrado / Clinica Medica / Mestra em Clínica Médica
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Avaliação da história evolutiva do gene HLA-G por meio de polimorfismos de base única e da inserção AluyHG / Evaluation of the HLA-G gene history by single-based polymorphisms and AluyHG insertionSantos, Kaisson Ernane dos 25 November 2013 (has links)
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Previous issue date: 2013-11-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The Major Histocompatibility Complex is mainly composed by genes of the adaptive
immune response. In humans, part of this complex is known as the Human Leukocyte
Antigens (HLA), whose genes are responsible for specific antigen presentation to effector
immune cells. The classical class I HLA genes (HLA-A, -B and -C) are responsible for
antigen presentation to T CD8+ cells and they constitute the most polymorphic genes in
the human genome. This variability is maintained by selection mediated by
microorganisms. In contrast to their classical counterparts, the non classical class I genes
(HLA-G, -E and -F) present low variability and are associated with immune tolerance due to
the interaction with NK and T cells inhibitor receptors. HLA-G is the most studied non
classical gene, which is associated with immune response modulation, mainly during
pregnancy. Considering that natural selection is acting on the HLA-G regulatory regions
maintaining high heterozigosity in this region, we evaluated a nearby Alu insertion
(AluyHG) correlating this Alu element with coding and 3’UTR HLA-G polymorphisms. The
AluyHG insertion was particularly associated with the HLA-G haplotype known as
G*01:01:01:01/UTR-1, considered a high-expressing HLA-G haplotype. The
G*01:01:01:01/UTR-1/AluyHG haplotype would be the most recent HLA-G haplotypes, in
spite of its high frequency in worldwide populations. / O Complexo Principal de Histocompatibilidade (MHC) é formado principalmente por
genes que participam da resposta imunológica adaptativa. Entre esses genes encontramos
o grupo denominado de Antígenos Leucocitários Humanos (HLA), que são responsáveis pela
apresentação de antígenos específicos às células efetoras do sistema imunológico. Os genes
HLA de classe I clássicos (HLA-A, -B e -C), responsáveis pela apresentação antigênica aos
linfócitos T citotóxicos, são considerado como os mais polimórficos do genoma humano e de
outros vertebrados. A variabilidade desses genes e elevada heterozigose é mantida por
seleção mediada por microrganismos. Diferentemente dos genes clássicos, os genes HLA de
classe I não clássicos (HLA-G, -E e -F) apresentam variabilidade reduzida e como função
principal a tolerância imunológica, por meio de sua interação com receptores inibitórios
presentes nas células NK e T. O HLA-G é o mais estudado entre esses genes e, devido sua
importância como molécula imunomoduladora e sua importância em situações como
gestação, e considerando evidências anteriores de seleção natural mantendo uma elevada
heterozigose nas regiões regulatórias do HLA-G, avaliamos a presença de uma inserção Alu
(AluyHG) próxima a este gene correlacionando os achados com a variabilidade contida nas
suas regiões codificadora e 3’ não traduzida. A inserção AluyHG mostrou-se em
desequilíbrio de ligação (LD) com os polimorfismos do gene HLA-G. Especificamente, o
elemento inserido apresentou-se em LD com um haplótipo denominado
G*01:01:01:01/UTR-1, considerado como um haplótipo de alta produção da molécula de
HLA-G. Esse haplótipo aparentemente é o mais jovem entre humanos, apesar de sua
elevada frequência nas populações estudadas até o momento.
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Utilização de células de trofoblasto de embriões partenogenéticos na descrição de haplótipos de BoLA-DRB3-DQA-DQBSÁ, André Luiz Alves de 30 March 2015 (has links)
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Previous issue date: 2015-03-30 / A perspectiva de aumentar a produtividade do gado bovino a partir da aplicação de melhoramento genético do rebanho é cada vez mais estudada. Dentre as regiões genômicas mais estudadas e promissoras têm-se o Complexo Principal de Histocompatibilidade (MHC), já que este reúne genes importantes na resposta imunológica do animal, sendo possível selecionar marcadores nesta região para maior resistência a enfermidades e, portanto, maior produção pecuária. A diversidade do MHC bovino, conhecido como BoLA (Bovine Leukocyte Antigens), foi estudada inicialmente investigando seus genes isoladamente. A maioria dos bovinos são heterozigotos em BoLA e apenas em ocasiões especiais (animais homozigotos ou que possuam informação de pedigree) seu haplótipo pode ser caracterizado. Portanto, este trabalho objetivou desenvolver uma nova abordagem para descrever haplótipos de BoLA de vacas heterozigotas, utilizando células do trofoblasto de embriões partenogenéticos bovinos. Dois métodos para validação desta abordagem foram utilizados: um painel de 445 SNPs em BoLA foi informativo acerca do efeito que a recombinação meiótica apresenta na zigose da região; e a comparação de alelos de BoLA-DRB3 entre a fêmea bovina e sua célula trofoblástica partenogenética (CTP) demonstrou ser um método confiável e prático para a investigação de homozigose em BoLA. A partir de ambos os métodos, a metodologia desenvolvida aqui foi validada, já que CTPs homozigotas em BoLA foram derivadas de vacas heterozigotas, permitindo a descrição de haplótipos de BoLA. A análise detalhada da região de Classe IIa de BoLA-DRB3-DQA-DQB revelou a presença de 18 haplótipos distintos, sendo 16 destes nunca antes descritos. Além disso, dois alelos de DQA e um de DQB presentes nestes haplótipos são novos. O método descrito aqui foi mais eficiente do que a investigação por fêmeas homozigotas ou inferir a composição haplotípica baseada em informação de pedigree, além de evitar ambiguidades nos resultados. Novas pesquisas buscando a otimização deste método podem aumentar a sua eficiência e torná-lo mais facilmente aplicável a uma variedade de estudos genéticos, usando espécies diferentes e com finalidades distintas. / The prospect of increasing the productivity of cattle by means of genetic improvement is increasingly investigated. Among the most studied and and promising genomic regions is the Major Histocompatibility Complex (MHC), since it includes key genes of the immune response of the animals, being able to select makers in this region for increased disease resistance and therefore greater production. The diversity of the cattle MHC, known as BoLA (Bovine Leukocyte Antigens), has been primarily studied using variants of serological specificities or sequencing some of its genes. Most cattle are heterozygous at BoLA and only in special occasions (homozygous animals or animals for which pedigree information is available) can the haplotypes be characterized. Therefore, this study aims to develop a novel approach to describe BoLA haplotypes from heterozygous cows, using trophoblast cells from parthenogenetic bovine embryos derived from slaughterhouse ovaries. Two methods for validating this approach were used: a panel of 445 SNPs spanning BoLA region was informative on the effect of meiotic recombination on the region zigosity; and the comparison of BoLA-DRB3 alleles between the dam and its parthenogenetic embryo derived trophoblast cells (PEDTC) proved to be a reliable and practical method for investigating BoLA homozigosity. Using both methods, the approach presented here was validated, since BoLA homozygous PEDTC were derived from heterozygous cows, allowing the description of BoLA haplotypes. Detailed analysis of the BoLA Class IIa region identified 18 different BoLA-DRB3-DQA-DQB haplotypes, including 16 novel haplotypes. Furthermore, two DQA and one DQB alleles included in these haplotypes were novel. This method was more efficient than to look for homozygous cows or infer haplotype composition based on pedigree information, in addition to avoid ambiguities on the results. New researches aiming for the improvement of this method can increase its efficiency and make it more easily applicable for a variety of genetic studies, using different species and for other purposes.
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Variabilidade e história evolutiva do gene HLA-E / Variability and evolutionary history of HLA-E geneFelício, Leandro Prado 31 January 2013 (has links)
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Previous issue date: 2013-01-31 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The HLA-E locus is a Human Major Histocompatibility Complex (MHC) gene
associated with immune-modulation and suppression of the immune response by the
interaction with specific NK and T cell receptors. The HLA-E gene is considered the
most conserved locus in the human HLA; however, this low variability might be a
consequence of the scarce number of studies focusing this subject. In this mastering
thesis we assessed the HLA-E coding and 3’ untranslated region variability in a
group of individuals from Brazil and the results were evaluated together with data
from the 1000Genomes Consortium. Altogether, only 28 variation sites were found in
approximately 2724 bp evaluated. These variation sites were arranged into 33
haplotypes, most of them (98.2%) encoding one of the two HLA-E molecules found
worldwide, i.e., the molecules associated with the allele groups E*01:01 and E*01:03.
Interestingly, 85% of all haplotypes were represented by only three different
sequences, each of them associated with one of the main known HLA-E coding
alleles, E*01:01:01, E*01:03:01 and E*01:03:02, all of them found worldwide. This
phenomenon, together with the comparisons with other primate sequences, reveals
that these two main allele groups (and molecules) arose early before human
speciation, and indicates that E*01:03:01 might be the oldest allele. In addition, the
low nucleotide diversity found for the HLA-E coding and 3’UTR in worldwide
populations suggests that the HLA-E gene is in fact a conserved gene, which might
be a consequence of its key role in the modulation of the immune system. / O loco HLA-E é um gene do Complexo Principal de Histocompatibilidade
Humano (MHC), cujo produto está relacionado com a modulação e supressão da
resposta imunitária por meio da interação com receptores específicos das células
NK e linfócitos T. O gene HLA-E é considerado o loco menos polimórfico dos genes
do complexo HLA, no entanto, esta baixa variabilidade pode ser uma consequência
do pequeno número de estudos realizados sobre esse tema. No presente trabalho, a
variabilidade das regiões codificadoras e 3’ não traduzida do gene HLA-E foi
analisada em amostras brasileiras e os resultados foram comparados com dados
obtidos pelo projeto 1000Genomes. Considerando todas as populações avaliadas,
apenas 28 pontos de variação foram encontrados em uma região de
aproximadamente 2724-pb. Estes pontos de variação estão arranjados em 33
haplótipos diferentes, a maioria deles (98%) codificando uma das duas moléculas
HLA-E frequentemente encontradas, E*01:01 e E*01:03. Ainda, 85% dos haplótipos
encontrados foram representados por apenas três sequências diferentes, cada uma
deles associada a um dos principais alelos da região codificadora do gene HLA-E,
E*01:01:01, E*01:03:01 e E*01:03:02. Todas essas sequências foram encontradas
em todas as populações avaliadas. Este fenômeno, em conjunto com as
comparações envolvendo sequências de primatas, sugere que estes dois grupos de
alelos principais (e moléculas) surgiram antes da especiação e dispersão humana,
além de indicar que o alelo E*01:03:01 pode ser o mais antigo dentre os demais.
Ainda, a baixa diversidade nucleotídica encontrada para a região codificadora e 3'
NT do gene HLA-E em populações de todo o mundo sugere que este gene é, de
fato, bastante conservado, provavelmente devido ao seu papel chave na modulação
das respostas imunes.
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