ABSTRACT
The peopling of the Canary Islands has been widely debated. The mitochondrial DNA and Y-chromosome data support the idea of a Berber genetic origin coming from the North of Africa (maternal) and a later contribution of the Spanish invaders (paternal). The frequencies of the HLA class II alleles from the Tenerife Island (another Canary Island) have previously been published, postulating a Berber and Atlantic/Iberian contributions to the current population. The HLA class I and class II allele frequencies, haplotype frequencies and phylogenetic comparisons were performed in 215 unrelated individuals from Gran Canaria Island (belonging to the kidney transplant waiting list), with at least three generations of ancestors from Canary Islands, in order to study the different ethnical HLA contributions to the genetic background of the Canary Islanders. Results showed the presence of a compound HLA haplotype of putative Phoenician-Berber origin, A*33:01-C*08:02-B*14:02-DRB1*03:01-DQB1*02:01, likely coming from the combination of haplotypes A*30:02-C*05:01-B*18:01-DRB1*03:01-DQB1*02:01 and A*33:01-C*08:02-B*14:02-DRB1*01:02-DQB1*05:01 of North African (probably Berber) and West Asian Mediterranean (probably Phoenician) origins, respectively. The latter haplotypes and others from the same origin (Berber/Phoenician) are also present in the population studied. Besides, other contributions from the North of Europe, North England-Iberian (Atlantic contribution), and Western Europe/Mediterraneans (Spanish colonization) are also discussed. These data conclude that the current genetic background of the Canary Islands inhabitants has been generated over the years by different ways with an original Phoenician-Berber substrate and several genetic contributions generated in different invasions.
ABSTRACT
HLA-DQB1*02:02:01:02 has an intron sequences coming from a combination of DQB1*02:01:01 and DQB1*02:02:01:01.
Subject(s)
Alleles , HLA-DQ beta-Chains/genetics , Humans , SpainABSTRACT
HLA-DQB1*02:02:01:02 has an intron sequences coming from a combination of DQB1*02:01:01 and DQB1*02:02:01:01.
ABSTRACT
HLA-DQB1*03:03:02:04 and DQB1*03:03:02:02 alleles differ by a single point mutation in intron 2.
Subject(s)
Alleles , HLA-DQ beta-Chains/genetics , Point Mutation , Base Sequence , Codon , Fetal Blood/chemistry , Gene Expression , Genetic Loci , Histocompatibility Testing , Humans , Introns , Molecular Sequence Data , SpainABSTRACT
Generation of the HLA-A*80:01:01:01 allele has been analysed using its complete sequence. Direct comparison of the sequences and phylogenetic trees using the human leukocyte antigen (HLA)-A representative alleles and the major histocompatibility complex (MHC)-A sequences of non-human primates has been made. Results based on exon sequences confirm previously published, but considering only the sequences of the introns, two distinct regions can be differentiated. The first one comprises from the 5' untranslated region region to the first part of intron 3 sequence (shared with A2 family), and the second one includes the sequence from the end of intron 3 to intron 7 (shared with A1/A3/A11/A36/A30 family). Each of them clusters with Gorilla and Chimpanzee MHC-A sequences, respectively, suggesting an origin coming from a common ancestor to Gorilla and Chimpanzee.
Subject(s)
Alleles , Exons , HLA-A Antigens/genetics , Introns , Phylogeny , 5' Untranslated Regions , Animals , Base Sequence , Biological Evolution , Gorilla gorilla , HLA-A Antigens/classification , HLA-A Antigens/immunology , Humans , Molecular Sequence Data , Pan troglodytes , Polymorphism, Genetic , Protein Isoforms/classification , Protein Isoforms/genetics , Protein Isoforms/immunologyABSTRACT
HLA-G alleles follow a different pattern of polymorphism generation that those of the HLA classical I alleles. However, this polymorphism maintenance could have an evolutionary specific pathways based on non coding regions as introns, 14 bp deletion/insertion (exon 8) or promoter regions. For this reason, a systematic sequencing study of HLA-G promoter region was done in 36 individuals with a total of 15 different alleles. From the 12 sequences obtained, 7 were new sequences and not previously described. Results show that the sequences have three different patterns of evolution confirming the results obtained in the rest of the sequence regions (exons, introns and 3'UTR) where three different lineages were established. Only one of these lineages includes the non-human primate promoter sequences suggesting the possibility of this lineage could come directly from non-human primates while the other two could be generated after the speciation. More non-human primates MHC-G promoter sequences must be obtained to confirm this hypothesis. Expression and functional assays could be done considering the differences obtained in the promoter regions involving the HLA-G function (mRNA expression, isoforms).
Subject(s)
Evolution, Molecular , HLA-G Antigens/genetics , Polymorphism, Genetic , Promoter Regions, Genetic/genetics , 3' Untranslated Regions/genetics , Alleles , Animals , Exons/genetics , HLA-G Antigens/classification , Humans , Introns/genetics , Molecular Sequence Data , Phylogeny , Primates/genetics , Sequence Analysis, DNAABSTRACT
HLA-G*01:03:01:02 and G*01:03:01:01 differ by a two nucleotide changes in intron 3.
Subject(s)
Fetal Blood/metabolism , HLA-G Antigens/genetics , Introns , Polymorphism, Genetic , Alleles , Base Sequence , Cord Blood Stem Cell Transplantation/methods , Humans , Molecular Sequence Data , Polymerase Chain Reaction/methods , Sequence Analysis, DNA , Sequence Homology, Nucleic AcidABSTRACT
Several studies have indicated the gene conversion as the most important mechanism about the MHC polymorphism generation when intron sequences are studied. The data obtained confirm that the B*83:01 allele is generated by gene conversion event including exon 2 and partial intron 1 and 2 between B*44 and B*56 alleles.
Subject(s)
Gene Conversion , HLA-B Antigens/genetics , Polymorphism, Genetic , Base Sequence , Exons , Humans , Introns , Molecular Sequence Data , Sequence AlignmentABSTRACT
America first inhabitants and peopling are still debated. In order to increase knowledge about these questions, we have aimed to detect HLA genes of an Amerindian secluded community: Jaidukama, who lives in North Colombia Equatorial forest. HLA genotyping and extended haplotype calculations were carried out in 39 healthy individuals belonging to 13 families. HLA frequencies were compared to other Amerindians and worldwide populations by calculating genetic distances, relatedness dendrograms and correspondence analyses. Only four DRB1 alleles were found (*0404, *0407, *1402 and *1602); however a total of 17 Amerindian different extended class I-class II HLA haplotypes were directly counted from the family studies, nine of them were specific of Jaidukamas. Some of the alleles or group of alleles within an extended haplotype (i.e. DQB1-DRB1) were also found in Asians and Pacific Islanders, further supporting existence of Asian and Pacific gene flow with Amerindians or a common founder effect. It is further supported that HLA extended haplotypes vary faster than alleles in populations. It is concluded that this unique model of Amerindian secluded families study suggests that rapid HLA haplotype variation may be more important than allele variation for survival (starting immune responses). This work may also be useful for future transplant programs in the area.
Subject(s)
Alleles , Asian People/genetics , HLA Antigens/genetics , Haplotypes/genetics , Indians, South American/genetics , Native Hawaiian or Other Pacific Islander/genetics , Chromosomes, Human/genetics , Colombia , Gene Frequency/genetics , Geography , Humans , PhylogenyABSTRACT
Recombination between HLA-G*01010101/02 and HLA-G*01010201 generates HLA-G*010120.
Subject(s)
HLA Antigens/genetics , Histocompatibility Antigens Class I/genetics , Recombination, Genetic , Base Sequence , HLA-G Antigens , Humans , Molecular Sequence DataABSTRACT
HLA-G*01010301 and G*01010302 differ by a single point mutation in intron 5.
Subject(s)
HLA Antigens/genetics , Histocompatibility Antigens Class I/genetics , Polymorphism, Single Nucleotide , Alleles , Base Sequence , HLA-G Antigens , Histocompatibility Testing , Humans , Introns/genetics , Molecular Sequence Data , Protein Isoforms/genetics , Sequence Analysis, DNA , Sequence Homology, Nucleic AcidABSTRACT
Three nucleotide changes and one insertion in intron 2 upon human leucocyte antigen (HLA)-G*01010105 generate HLA-G*01010106.
Subject(s)
Alleles , HLA Antigens/genetics , Histocompatibility Antigens Class I/genetics , Introns/genetics , Base Sequence , DNA/genetics , DNA/isolation & purification , DNA Primers/genetics , Female , Fetal Blood/chemistry , Gene Conversion , HLA-G Antigens , Histocompatibility Testing/methods , Humans , Molecular Sequence Data , Mutagenesis, Insertional , Polymerase Chain Reaction , Polymorphism, Genetic , Pregnancy , Sequence Analysis, DNA/instrumentation , Sequence Analysis, DNA/methods , Terminology as TopicABSTRACT
Human leukocyte antigen (HLA)-E is a nonclassical class I (Ib) gene with a restricted polymorphism. Only eight DNA alleles and three proteins of this gene have been described and their frequencies analyzed in Caucasian, Oriental, Asian Indian, and Negroid populations. In the present study, HLA-E polymorphism has been analyzed in six Amerindian and Mestizo populations from North and South America and compared with previously described populations. HLA-E*0101 is the most frequent allele found in all populations except in Afrocolombian and Wayu Amerindians, in which blood group analyses show a high admixture with Caucasian and African populations. Mazatecan and Mapuche (two Amerindian groups from North and South America, respectively) presented similar HLA-E frequencies, whereas Wayu Indians are more similar to the Afrocolombian population. The Mexican and Colombian Mestizo show similar allele frequencies to Amerindians with high frequencies of HLA-E*0101 and HLA-E*010302 alleles. Also, frequencies in Negroids and Asian Indians present a similar distribution of HLA-E alleles. These data are in agreement with worldwide restricted polymorphism of HLA-E because no new allele was detected in the six populations studied. The allelic frequencies show differences among Caucasian, Oriental, Mestizo and Indian populations. Ape major histocompatibility complex-E allelism is also very restricted: common chimpanzee (one allele); bonobo (two alleles); gorilla (two alleles); orangutan (one allele); rhesus monkey (eight alleles); cynomolgus monkey (two alleles); and green monkey (two alleles).
Subject(s)
Asian People/genetics , Ethnicity/genetics , HLA Antigens/genetics , Histocompatibility Antigens Class I/genetics , Polymorphism, Genetic , White People/genetics , Alleles , Animals , Chile/ethnology , Colombia/ethnology , Gene Frequency , Hominidae/genetics , Humans , Mexico , Pan paniscus/genetics , Pongo pygmaeus/genetics , Protein Conformation , HLA-E AntigensABSTRACT
Six proteins, one null allele and 22 human leukocyte antigen (HLA)-G alleles were found in humans. Bonobo, chimpanzee and gorilla only show one allele and orangutan shows five alleles. All Cercopithecus alleles show stop codons at position 164 (Macaca mulatta with seven DNA alleles, Macaca fascicularis with seven DNA alleles and Cercopithecus aethiops with three DNA alleles). Cotton-top tamarin New World monkeys showed 20 DNA and protein alleles; the major histocompatibility complex (MHC)-G New World sequences seem to be closer to MHC-E and lack typical MHC-G primates intron 2-specific deletion. This seems to suggest that MHC-G genes in New World primates are not orthologous and that their function may be similar to that of classical presenting MHC genes.
Subject(s)
Biological Evolution , HLA Antigens/genetics , Histocompatibility Antigens Class I/genetics , Major Histocompatibility Complex/genetics , Polymorphism, Genetic , Animals , Base Sequence , Family , Female , HLA-G Antigens , Homozygote , Humans , Major Histocompatibility Complex/immunology , Male , Molecular Sequence Data , Pedigree , Primates/genetics , Sequence Homology, Nucleic AcidABSTRACT
El estudio de la genética de poblaciones se utiliza en epidemiologíay en medicina preventiva y predictiva, además de paraaveriguar el origen y el emparentamiento de los grupos étnicosen estudios antropológicos.El sistema más polimórfico en humanos es el complejo HLA,y unos pocos de sus alelos están ligados a enfermedad. En este sentido,los marcadores genéticos más utilizados para estudios antropológicos,las variantes de DNA mitocondrial y del cromosoma Y,también están ligadas a enfermedades, pero en un grado comparativamentemayor que HLA, teniendo en cuenta solamente elnumero de «alelos sanos» de estos marcadores genéticos. El estudiode los genes HLA demuestra que es muy útil para descubrir elorigen y el emparentamiento genético de las poblaciones a nivelmundial. En el presente estudio, hemos comprobado cómo, aparentemente,los Amerindios no se relacionan genéticamente conninguna otra población del mundo. De acuerdo con los genes HLA,los Amerindios son los primeros habitantes de las Américas y estabanallí cuando llegaron oleadas de gentes hablando lenguas NaDene (Atabascos, Navajos, Apaches) y Esquimales. Mientras seobserva que en todas las otras poblaciones mundiales existe ungradiente de emparentamiento, que va en general concordandocon la proximidad o lejanía geográfica, los Amerindios se sitúanaparte de todos. Esta conclusión principal se ha basado en el estudiode 14.968 cromosomas HLA de todo el mundo y en análisisestadísticos utilizando el método de «Neighbour Joining» y los análisisde correspondencia, junto con las distancias genéticas de Neientre grupos étnicos. El estudio poblacional HLA de Amerindiosprocedentes de la zona del Océano Pacífico sudamericano es particularmenteimportante para España, donde se viene registrandoun importante flujo migratorio procedente de estos países. Estohace necesario hacer listas de tipaje HLA con el objeto de efectuartrasplantes entre españoles y Amerindios para fines terapeúticos
The genetic profiles of human populations are being used forepidemiology and preventive/predictive medicine, in additionto ascertaining the origin and relatedness of ethnic groups foranthropological studies.HLA is the most polymorphic genetic system in humans anda few HLA alleles are linked to disease. However, the mtDNAand Chr Y variants, widely used in genetic anthropology, are linkedto disease to a much higher degree than HLA, if we only takeinto account the number of «healthy» alleles from these three differentgenetic markers.HLA gene studies allow the determination of the origin andgenetic relatedness of worldwide populations. In the present studywe have been able to uncover that Amerindians apparently donot relate with any other worldwide population, according totheir HLA genetic profile. Amerindians are the very First AmericanNatives that were already in America when Na Dene (Athabascans,Navajo, Apache) and Eskimo speaking people reachedit. While other worldwide populations are genetically related followinggenerally a smooth geographic gradient, Amerindians appearapart. This main conclusion has been reached by using 14,968worldwide HLA chromosomes and Neighbour Joining and correspondenceanalyses together with Nei´s genetic distances betweenethnic groups. The HLA study of southern American PacificAmerindians is particularly important for Spain, where a recentimportant immigration of these populations has taken place. Thismakes it necessary to building up an Amerindian typing list inSpain in order to deal with transplantation between Spaniardsand Amerindians for therapeutic uses
Subject(s)
Humans , American Indian or Alaska Native/genetics , Major Histocompatibility Complex/genetics , Ethnicity/genetics , Inuit/genetics , Diabetes Mellitus, Type 1/genetics , Organ Transplantation/ethnologyABSTRACT
The generation of the B*41 alleles has been analysed using exon 1, intron 1, exon 2, intron 2 and exon 3 sequences. Results showed that B*4102 may have been generated as the first B*41 allele by a recombination mechanism between B*400102 and B*0801 or B*4201 involving intron 2. B*4101, B*4104 and B*4107 alleles could have been generated from B*4102 by a gene conversion event taking three different fragments from sequences belonging to intron 2/exon 3 of B*45, B*50 or B*49 alleles. B*4105 and B*4106 could be generated from B*4101 allele by point mutations, and B*4103 generation is unclear due to the lack of intron 2. The importance of introns in HLA-B allele polymorphism generation is stressed.
Subject(s)
Alleles , HLA-B Antigens/genetics , Introns/genetics , Recombination, Genetic , Base Sequence , Humans , Molecular Sequence Data , Polymorphism, Genetic , Sequence Alignment , Sequence Homology, Nucleic AcidSubject(s)
Alleles , Major Histocompatibility Complex/genetics , Primates/genetics , Animals , Base Sequence , Cell Line , Evolution, Molecular , Exons , Gorilla gorilla/genetics , Gorilla gorilla/immunology , Humans , Introns , Major Histocompatibility Complex/immunology , Molecular Sequence Data , Pan paniscus/genetics , Pan paniscus/immunology , Pan troglodytes/genetics , Pan troglodytes/immunology , Polymorphism, Genetic , Pongo pygmaeus/genetics , Pongo pygmaeus/immunology , Primates/immunology , Sequence AlignmentABSTRACT
The major histocompatibility complex (MHC)-F class Ib locus shows a limited polymorphism, and the function of its mainly intracellular protein is not clear. We have identified human leucocyte antigen (HLA)-F orthologous DNA sequences in Pongidae in order to study the MHC-F gene evolution and its products' function. HLA-F orthologous cDNA transcripts are found in chimpanzee and in the new primate species studied (bonobo, gorilla and orangutan). Analyses of the predicted amino acid sequences and their comparison with other primate MHC-F proteins show that MHC-F may be a protein with a typical class I structure and that the key residues of the peptide-binding region (PBR) are highly conserved in MHC-F in all studied primates species. Thus, MHC-F conservation along the primate evolution suggests an important role in cellular physiology. It is possible that the MHC-F protein could be involved, together with MHC-G and MHC-E, in the natural killer (NK) cell activity regulation, although rhesus macaque does not express MHC-G and MHC-E orthologues. The evolutionary pathway of the six-base-pair deletion at exon 2 existing in some primates is put forward.
Subject(s)
Evolution, Molecular , Exons/genetics , Genes, MHC Class I/genetics , Quantitative Trait Loci/genetics , Sequence Deletion/genetics , Amino Acid Sequence , Animals , Cell Line , Exons/immunology , Genes, MHC Class I/immunology , Hominidae , Humans , Molecular Sequence Data , Quantitative Trait Loci/immunology , Sequence Analysis, Protein/methods , Sequence Deletion/immunologyABSTRACT
Aymara Amerindians from the Titicaca Lake Andean highlands are studied for HLA-A, HLA-B, HLA-DRB1 and HLA-DQB1 gene frequencies. Genetic distances, neighbour-joining and correspondence analyses are performed by using other Amerindian and worldwide populations (15384 chromosomes are studied). The HLA genetic profile of Aymaras is different from neighbouring and language-related Quechuas (Incas). Both Quechuas and Aymaras seem to present an HLA-DRB1*0901 high frequency, which is present in a very low frequency or absent in Mesoamericans (Mazatecans, Mayans) and most studied Amerindians. Moreover, it is observed a closer relatedness of Aymaras with Amerindians from the Amazon Basin and Chaco lowlands, compared to Quechuans.
Subject(s)
American Indian or Alaska Native/genetics , HLA Antigens/genetics , Histocompatibility Antigens Class II/genetics , Histocompatibility Antigens Class I/genetics , Bolivia , Gene Frequency , Haplotypes , HumansABSTRACT
The HLA allele frequency distribution of the Mayans from Guatemala was studied and compared with those of other First American Natives and worldwide populations (a total of 12,364 chromosomes and 6182 individuals from 60 different populations). The main conclusions were (1): the closest Amerindian group to Mayans is the Arhuacs, who were the first recorded Caribbean Islands' inhabitants (2). Mayans are not so close to Mesoamerican Zapotec, Mixe and Mixtec Amerindians, who genetically cluster together. Mixe had been related to Mayans only on linguistic bases (3). DRB1*0407 and DRB1*0802 alleles are found in 50% of Mayans; these alleles are also found in other Amerindians, but the Mayans' high frequencies may be showing a founder effect for this Mesoamerican-Caribbean population (4). Extended Mayan specific HLA haplotypes are described for the first time (5). Language and genes do not completely correlate in microgeographical studies (6). Significant genetic input from outside is not noticed in Meso and South American Amerindians according to the genetic analyses; while all world populations (including Africans, Europeans, Asians, Australians, Polynesians, North American Na-Dene Indians and Eskimos) are genetically related. Meso and South American Amerindians tend to remain isolated in the neighbour joining analyses.
