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1.
Sci Rep ; 13(1): 16711, 2023 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-37794053

RESUMO

HLA and disease studies by using single allele statistics have been fruitless during the last 40 years for explaining association pathogenesis of the associated diseases.Other approaches are necessary to untangle this puzzle. We aim to revisit complement alleleism in humans and primates for both studying MHC and disease association to complotypes and extended MHC haplotypes in order to also explain the positive directional selection of maintaining immune response genes (complement, MHC adaptive and MHC non-specific genes) that keeps these three type of genes together in a short chromosome stretch (MHC) for million years. These genes may be linked to conjointly avoid microbes attack and autoimmunity. In the present paper, it is obtained a new Bf chimpanzee allele, provisionaly named Patr-Bf*A:01,that differs from other Bf alleles by having CTG at eleventh codon of exon 2 in order to start the newly suggested methodology and explain functional and evolutionary MHC obscure aspects. Exons 1 to 6 of Ba fragment of Bf gene were obtained from chimpanzee. This new chimpanzee Factor B allele (Patr-Bf*A:01) is to be identical to a infrequent human Bf allele (SNP rs641153); it stresses the strong evolutive pressure upon certain alleles that are trans specific. It also may apply to MHC extended haplotipes which may conjointly act to start an adequate immune response. It is the first time that a complement MHC class III allele is described to undergo trans species evolution,in contrast to class I and class II alleles which had already been reported . Allelism of complement factors are again proposed for studying MHC complement genes, complotypes, and extended MHC haplotypes which may be more informative that single MHC marker studies.


Assuntos
Hominidae , Pan troglodytes , Masculino , Animais , Humanos , Alelos , Pan troglodytes/genética , Complexo Principal de Histocompatibilidade/genética , Hominidae/genética , Antígenos de Histocompatibilidade , Fator B do Complemento/genética , Cromossomos
2.
Sci Rep ; 13(1): 16203, 2023 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-37758772

RESUMO

The contribution of migrated people from once green Sahara (about 10,000-6000 years BC) towards Mediterranean area had probably a double effect: both genetic and cultural connections have been described between Western Europe and North Africa. Sudanese populations from different ethnicities have been studied for HLA-A, -B, -DRB1 and -DQB1 antigens by a standard microlymphotoxicity method. Results found show that Nubians are genetically related with African Sub-Saharan populations and distant from other Sudanese tribes, who are closer to Mediterranean populations than to Sub-Saharan ones. This is concordant with other authors and meta-analysis data. Our present work is, to our knowledge, the first and only one HLA research that studies Sudanese people according to different Sudan ethnic groups: samples were collected before Sudan partition between North and South. A prehistoric genetic and peoples exchange between Africa and the Mediterranean basin may be observed and is supported with the results obtained in this Sudanese HLA study. However, demic diffusion model of agriculture and other anthropological traits from Middle East to West Europe/Maghreb do not exist: a more detailed Sahel and North African countries ancient and recent admixture studies are also being carried out which may clearer explain pastoralists/agriculture innovations origins in Eurafrican Mediterranean and Atlantic façade.


Assuntos
População Negra , Grupos Raciais , Humanos , Haplótipos/genética , Alelos , Sudão
3.
Hum Immunol ; 83(11): 739-740, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35987703

RESUMO

Georgia (or Sakartvelo in its own language) is a South Caucasus Mts. country with its easternmost part is enigmatically named Iberia, like the Iberian Peninsula, which may refer to rivers "Kura" and "Ebro" or their valleys respectively. Most of their inhabitants speak Georgian which is included within Dene-Caucasian group and Usko-Mediterranean subgroup of languages. The latter includes Basque, Berber, ancient Iberian-Tartessian, Etruscan, Hittite, Minoan Lineal A and others. In the present paper, HLA class II -DRB1 and -DQB1 alleles has been studied and extended haplotypes calculated. Most frequent haplotypes are also of Mediterranean origin (i. e.: (A*02-B*51)-DRB1*11:01-DQB1*03:01, (A*02-B*51)-DRB1*13:01-DQB1*06:03, or (A*24-B*35)-DRB1*01:01-DQB1*05:01) and DA genetic distances show that closest world populations to Georgians are Mediterraneans. Georgians also show common extended haplotypes ((A*02-B*51)-DRB1*11:01-DQB1*03:01, (A*02-B*13)-DRB1*07:01-DQB1*02:01 and (A*03-B*35)-DRB1*11:01-DQB1*03:01) with Svan people, a secluded population in North Georgia mountains. We can conclude that Georgians belong to a very old Mediterranean substratum according to both linguistics (Usko Mediterranean languages) and HLA genetics.


Assuntos
Cadeias HLA-DRB1 , Humanos , Frequência do Gene , República da Geórgia , Haplótipos , Cadeias HLA-DRB1/genética
4.
Hum Immunol ; 83(6): 477-479, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35459551

RESUMO

Azeri people are at present day mainly living in an area which comprises North (Azerbaijan) and South (Azeri Iran provinces) parts, living the biggest population in Azeri Iran provinces with about 17-20 million people. They were studied HLA-A, -B, -DRB1 and -DQB1 allele and extended haplotype frequencies in unrelated Iranian Tabriz Azeris from a rural area close to Tabriz City. The HLA extended haplotypes with highest frequencies are: 1) HLA- A*24:02-B*35:01-DRB1*11:01-DQB1*03:01, shared with Mediterraneans and southern Russians (Chuvash, which also show Mediterranean characters); and 2) HLA-A*01:02-B*08:01-DRB1*03:01-DQB1*02:01, found also in Chuvash and other Azeri samples from Tabriz. Neí's DA HLA-DRB1 genetic distances, HLA-DRB1 Neighbour-Joining dendrogram and Vista analyses show that population with closest distance is Kurdish, followed by Iranian Gorgan and Southern Russia/ North Caucasus Chuvash; probably these latter groups and Azeris were populating North Mesopotamia/ Caucasus Mts. since prehistoric times. Kurds (in Iraq and Iran) do not speak Turk while Azeris do: they are both genetically close, but they are not genetically close to present day Anatolia (Turkey) Turks who also speak Turk language and show a typical Mediterranean HLA profile. In summary, Azeri population studies show examples that genes and languages do not correlate, contradicting the postulate asserted by others.


Assuntos
Etnicidade , Genética Populacional , Antígenos de Histocompatibilidade , Idioma , Alelos , Etnicidade/genética , Frequência do Gene , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Cadeias beta de HLA-DQ/genética , Cadeias HLA-DRB1/genética , Haplótipos , Antígenos de Histocompatibilidade/genética , Humanos , Irã (Geográfico)
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