PubMed Health⌕ Search

Biomedical subjects

J Moscoso

Publications and source records attributed to J Moscoso.

At least 19 recordsLinked to original sources

HLA-G, -E and -F: allelism, function and evolution.

The major histocompatibility complex class I genes comprise a bunch of classical genes (A, B, C), non-classical genes (E, F and G), pseudogenes and truncated genes. MHC-E, -F and -G are now considered immune "tolerization" molecules, which not only interact with NK cells but with T lymphocyte subsets and other cells and have a role in fetus acceptation. A strong positive directional selection is acting for maintaining the observed low polymorphism on E, F and G loci in human and apes. Invariance must be important for this non-classical class I proteins function.

Alleles↗

Generation of the B*41 group of alleles as indicated by intron sequences.

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.

Alleles↗

High-resolution molecular characterization of the HLA class I and class II in the Tarahumara Amerindian population.

We describe for the first time the high-resolution profiling of HLA-A, -B, -C, -DRB1, -DQB1 and -DPB1 in a culturally and geographically distinct Mexican ethnic group, the Tarahumaras. The alleles most frequently found by reference strand-mediated conformational analysis in this population were for class I: HLA-A*240201, *020101/09, *0206, *310102, *680102; HLA-B*4002, *1501, *510201, *3501/02/03, *4005, *4801; HLA-Cw*0304, *0801, *0102, *040101; and for class II: HLA-DRB1*080201, *1402, *040701; HLA-DQB1*0402, *0301, *0302/07; HLA-DPB1*0402, *0401, *020102. In addition, a novel allele, HLA-A*0257, was found. Based on comparison of presently known HLA-DRB1 and -DQB1 allele frequencies in Amerindian groups and worldwide populations, the Tarahumaras are unexpectedly more related to the geographically and linguistically distant Aymara and Terena Amerindian groups than they are to neighbouring tribes.

Ethnicity↗

Origin of Aymaras from Bolivia and their relationship with other Amerindians according to HLA genes.

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.

American Indian or Alaska Native↗

MHC-F DNA sequences in bonobo, gorilla and orangutan.

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.

Amino Acid Sequence↗

HLA class I allele distribution of a Hong Kong Chinese population based on high-resolution PCR-SSOP typing.

A stem cell registry population from Hong Kong, of Chinese ethnicity, was examined for HLA-A and HLA-B alleles using a two-stage sequence-specific oligonucleotide probe system. Comparison of the HLA-A and HLA-B frequencies with different populations showed a close relationship with a Chinese population from Singapore, although there were several differences in the presence/absence of alleles at the HLA-B locus. Having the data available on these registry donors will influence the search strategy and the ongoing compilation of new donors to the registry. In addition, knowing which alleles do/do not occur in this population will aid in the distinction of ambiguities which result from the use of many of the typing kits available.

Alleles↗

Origin of Mayans according to HLA genes and the uniqueness of Amerindians.

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.

Alleles↗

HLA alleles in isolated populations from North Spain: origin of the Basques and the ancient Iberians.

HLA-A, -B, -DRB1, -DQA1 and -DQB1 alleles have been studied in three relatively isolated populations of northern Spain from Cantabria ( Pas Valleys inhabitants or Pasiegos and Cabuernigos) and from the Basque Country (Arratia Valley inhabitants). These populations have been compared with neighbouring ones and other Mediterraneans by using neighbour-joining dendrograms and plane genetic distances.

Alleles↗

The origin of Palestinians and their genetic relatedness with other Mediterranean populations.

The genetic profile of Palestinians has, for the first time, been studied by using human leukocyte antigen (HLA) gene variability and haplotypes. The comparison with other Mediterranean populations by using neighbor-joining dendrograms and correspondence analyses reveal that Palestinians are genetically very close to Jews and other Middle East populations, including Turks (Anatolians), Lebanese, Egyptians, Armenians, and Iranians. Archaeologic and genetic data support that both Jews and Palestinians came from the ancient Canaanites, who extensively mixed with Egyptians, Mesopotamian, and Anatolian peoples in ancient times. Thus, Palestinian-Jewish rivalry is based in cultural and religious, but not in genetic, differences. The relatively close relatedness of both Jews and Palestinians to western Mediterranean populations reflects the continuous circum-Mediterranean cultural and gene flow that have occurred in prehistoric and historic times. This flow overtly contradicts the demic diffusion model of western Mediterranean populations substitution by agriculturalists coming from the Middle East in the Mesolithic-Neolithic transition.

Alleles↗

HLA molecular markers in Tuvinians: a population with both Oriental and Caucasoid characteristics.

HLA class I and class II alleles have been studied for the first time in the Turkish-speaking Tuvinian population, which lives in Russia, North of Mongolia and close to the Altai mountains. Comparisons have been done with about 11000 chromosomes from other worldwide populations, and extended haplotypes, genetic distances, neighbor joining dendrograms and correspondence analyses have been calculated. Tuvinians show an admixture of Mongoloid and Caucasoid characters, the latter probably coming from the ancient Kyrgyz background or, less feasibly, more recent Russian Caucasoid admixture. However, Siberian population traits are not found and thus Tuvinians are closer to Central Asian populations. Siberians are more related to Na-Dene and Eskimo American Indians; Amerindians (from nowadays Iberian--America) are not related to any other group, including Pacific Islanders, Siberians or other American Indians. The 'more than one wave' model for the peopling of the Americas is supported.

Alleles↗

HLA genes in Macedonians and the sub-Saharan origin of the Greeks.

HLA alleles have been determined in individuals from the Republic of Macedonia by DNA typing and sequencing. HLA-A, -B, -DR, -DQ allele frequencies and extended haplotypes have been for the first time determined and the results compared to those of other Mediterraneans, particularly with their neighbouring Greeks. Genetic distances, neighbor-joining dendrograms and correspondence analysis have been performed. The following conclusions have been reached: 1) Macedonians belong to the "older" Mediterranean substratum, like Iberians (including Basques), North Africans, Italians, French, Cretans, Jews, Lebanese, Turks (Anatolians), Armenians and Iranians, 2) Macedonians are not related with geographically close Greeks, who do not belong to the "older" Mediterranenan substratum, 3) Greeks are found to have a substantial relatedness to sub-Saharan (Ethiopian) people, which separate them from other Mediterranean groups. Both Greeks and Ethiopians share quasi-specific DRB1 alleles, such as *0305, *0307, *0411, *0413, *0416, *0417, *0420, *1110, *1112, *1304 and *1310. Genetic distances are closer between Greeks and Ethiopian/sub-Saharan groups than to any other Mediterranean group and finally Greeks cluster with Ethiopians/sub-Saharans in both neighbour joining dendrograms and correspondence analyses. The time period when these relationships might have occurred was ancient but uncertain and might be related to the displacement of Egyptian-Ethiopian people living in pharaonic Egypt.

Africa, Northern↗

HLA alleles and haplotypes in the Turkish population: relatedness to Kurds, Armenians and other Mediterraneans.

Turkish and Kurdish HLA profiles are studied for the first time. The comparative study of their allele frequencies, characteristic haplotypes, genetic distances with other Mediterraneans is complemented by neighbor-joining dendrograms and correspondence analyses. Turks, Kurds, Armenians, Iranians, Jews, Lebanese and other (Eastern and Western) Mediterranean groups seem to share a common ancestry: the older "Mediterranean" substratum. No sign of the postulated Indo-European (Aryan) invasion (1200 B.C.) is detected by our genetic analysis. It is concluded that this invasion, if occurred, had a relatively few invaders in comparison to the already settled populations, i.e. Anatolian Hittite and Hurrian groups (older than 2000 B.C.). These may have given rise to present-day Kurdish, Armenian and Turkish populations.

Alleles↗

The evolution of the MHC-G gene does not support a functional role for the complete protein.

The study of the MHC-G gene evolution during nearly 40 million years does not support a role for the full molecule. The MHC-G-like proteins of New World monkeys are probably classical presenting molecules. Old World Cercopithecinae monkeys do not have a full MHC-G molecule and human individuals homozygous for the HLA-G null allele are healthy and do not show birth pathologies.

Amino Acid Sequence↗

Lack of MHC-G4 and soluble (G5, G6) isoforms in the higher primates, Pongidae.

HLA-G is a class Ib (nonclassical) major histocompatibility complex (MHC) protein expressed at the materno-fetal interface that may inhibit natural killer (NK) cell-mediated lysis in an allotype-independent manner. The human MHC-G transcript is differentially spliced, giving rise to at least six different forms. In order to study the evolutionary importance of this phenomenon, the presence of alternative splicing in MHC-G mRNA molecules from Pongidae (Chimpanzee, Gorilla, and Orangutan) has been investigated in the present work, and three alternative spliced isoforms (i.e.: G1, G2, and G3) have been found, but not the G4 and the soluble G5 and G6 ones. In addition, a novel MHC-G isoform is described in Gorilla, "G2 short." This molecule is similar to the G2 isoform, but it lacks 29 amino acids normally encoded by exon 4. Our findings suggest that soluble isoforms are not necessary for MHC-G function(s) in Pongidae or that MHC-G is not a functional protein, because G1 is not necessary for survival in humans and Cercopithecinae bear stop codons in MHC-G exon 3.

Animals↗

Perinatal management of unanticipated congenital laryngeal atresia.

Unless ventilation is achieved within minutes of delivery, patients with congenital laryngeal atresia will not survive. There are 2 settings in which survival is more likely: a tracheotomy may be immediately performed in the delivery room, or a communication may exist between the airway and the pharynx, allowing for air exchange. In the latter case, there are no characteristic findings on prenatal sonography to suggest the diagnosis and to ensure that preparations for immediate tracheotomy are made. We describe a neonate with unanticipated laryngeal atresia and a high tracheoesophageal fistula. Ventilation was maintained first by face mask and then by esophageal intubation until a tracheotomy could be performed. This report provides detailed photodocumentation of the anomaly, discusses the mechanism of air exchange, reviews the relevant embryological development, and outlines a protocol for perinatal management of unanticipated laryngeal atresia.

Female↗