Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21
Filtrar
1.
Int J Legal Med ; 137(4): 1017-1022, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37209137

RESUMEN

This work presents the results of a DNA test aimed to determine a possible biological link of paternal half brotherhood of two males. The combined use of biparentally inherited markers (autosomal STRs) and a panel of 27 Y-STRs allowed us to determine the existence of a biological relationship of kinship, even after detecting three mutations at their Y-STR haplotypes along the analyses, constituting an infrequent multiple mutation situation. This case is an example illustrating the importance of having different analytical markers sets and strategies for clarifying complex kinship cases where mutations occur.


Asunto(s)
Repeticiones de Microsatélite , Hermanos , Masculino , Humanos , Haplotipos , Genotipo , Cromosomas Humanos Y , Mutación , Dermatoglifia del ADN , Genética de Población
2.
Lett Appl Microbiol ; 73(3): 308-317, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34048079

RESUMEN

Sequence analysis of the ORFK1 of human herpesvirus type 8 (HHV-8) allows the identification of six major subtypes (A-F), which are related to human migrations and the clinical progression of Kaposi's sarcoma. Sequencing and subsequent phylogenetic analysis of ORFK1 is considered to be the most reliable method for HHV-8 genotyping. However, it exhibits challenges and limitations. Herein, we designed and validated a single base extension (SBE) protocol for characterization of HHV-8 ORFK1 subtypes. A nested polymerase chain reaction (PCR) protocol was carried out to amplify a small 294-bp PCR product encompassing four single nucleotide polymorphisms at positions 360, 406, 465 and 527 of the HHV-8 genome. Finally, a multiplex SBE technique was developed and validated in 20 samples previously genotyped by phylogenetic analysis. The patterns obtained in this reaction could successfully discriminate between ORFK1 subtypes. The typing results obtained completely matched with those of the 'gold standard' method in all analysed samples. This method can reliably identify HHV-8 subtypes A, B and C, which are the most prevalent ones worldwide, and the remaining subtypes (D, E and F). SBE can be useful as an efficient, rapid and low-cost screening method for viral genotyping in a single tube, particularly samples with low-quality DNA, and with easy data interpretation.


Asunto(s)
Herpesvirus Humano 8 , Sarcoma de Kaposi , ADN Viral/genética , Genotipo , Herpesvirus Humano 8/genética , Humanos , Filogenia
3.
Mol Genet Genomics ; 296(3): 581-590, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33580820

RESUMEN

Aiming to determine their ancestry diagnostic potential, we selected two sets of nuclear deletion/insertion polymorphisms (DIPs), including 30 located on autosomal chromosomes and 33 on the X chromosome. We analysed over 200 unrelated Argentinean individuals living in urban areas of Argentina. As in most American countries, the extant Argentinean population is the result of tricontinental genetic admixture. The peopling process within the continent was characterised by mating bias involving Native American and enslaved African females and European males. Differential results were detected between autosomal DIPs and X-DIPs. The former showed that the European component was the largest (77.8%), followed by the Native American (17.9%) and African (4.2%) components, in good agreement with the previously published results. In contrast, X-DIPs showed that the European genetic contribution was also predominant but much smaller (52.9%) and considerably larger Native American and African contributions (39.6% and 7.5%, respectively). Genetic analysis revealed continental genetic contributions whose associated phenotypic traits have been mostly lost. The observed differences between the estimated continental genetic contribution proportions based on autosomal DIPs and X-DIPs reflect the effects of autosome and X-chromosome transmission behaviour and their different recombination patterns. This work shows the ability of the tested DIP panels to infer ancestry and confirm mating bias. To the best of our knowledge, this is the first study focusing on ancestry-informative autosomal DIP and X-DIP comparisons performed in a sample representing the entire Argentinean population.


Asunto(s)
Cromosomas Humanos Y/genética , Etnicidad/genética , Polimorfismo Genético/genética , Argentina , Población Negra/genética , Femenino , Genética de Población/métodos , Humanos , Masculino , Población Blanca/genética
5.
Int J Legal Med ; 133(5): 1309-1320, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30737602

RESUMEN

The Y chromosome behaves as a single locus. Its genetic information is useful in forensic casework, deficiency kinship testing, and population genetics studies. Continuous increases of loci number within commercial kits forced modification of worldwide reference databases. In Pan American countries, like Argentina, diverse parental ethnic groups contributed to the extant admixed urban populations. We report 509 additional haplotypes of 23 Y-STRs from donors inhabiting urban areas of six Argentinean provinces: Buenos Aires, Santiago del Estero, Santa Cruz, Rio Negro, Santa Fe, and Formosa. To better understand the demographic landscape of the admixed urban paternal lineages, structural analysis was performed using published data from other Argentinean provinces. AMOVA by Rst distance and inferred haplogroups by two predictive online software methods based on haplotypes yielded complementary results with respect to detected population structure, probably due to the different proportions of the Native American Q3-M3 haplogroup in the studied samples. This situation, which is common to most North, Meso, and South American countries, underscores the need for the additional step of typing specific SNPs for haplogroup diagnosis. We propose organizing Y-STR haplotype reference databases according to the most frequent haplogroups detected in a given admixed population.


Asunto(s)
Cromosomas Humanos Y , Bases de Datos Genéticas , Etnicidad/genética , Haplotipos , Repeticiones de Microsatélite , Argentina/etnología , Genética Forense , Genética de Población , Humanos , Masculino , Polimorfismo de Nucleótido Simple , Población Urbana
6.
Int J Legal Med ; 131(1): 107-112, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27282766

RESUMEN

Polymorphic genetic markers located on the X chromosome might become a complement in particular forensic identification when the biological kinship are deficient. We analyzed forensic statistical parameters of 33 X-chromosome InDel polymorphisms in a sample of 320 individuals from Argentina. The X-chromosome InDel polymorphism (X-InDel) panel was amplified in a single multiplex PCR reaction. Hardy-Weinberg Equilibrium was determined in the female cohort, whereas the male cohort was used to calculate linkage disequilibrium (LD) tested by an extension of Fisher's exact test, D', and Chi-square values. Regarding LD, 15 markers were organized and grouped into six blocks containing two or three linked loci each, namely block I (MID356-MID357), block II (MID448804-MID3703-MID218), block III (MID3705-MID3706-MID304737), block IV (MID197147-MID3754), block V (MID3664-MID284601-MID103547), and block VI (MID3763-MID3728). The haplotype diversity was higher than 0.99 in all cases. Blocks III and VI showed the highest match probability in the studied population, whereas block II showed the lowest. The accumulated power of discrimination was 99.9999991 % in women and 99.9992925 % in men. The mean exclusion chance in trios and duos were 99.9891736 and 99.6099391 %, respectively. Since 15 markers are associated as haplotypic blocks, for a conservative treatment of the data, statistical evaluation should consider their haplotypic frequencies and the remaining 18 markers can be evaluated as independent loci.


Asunto(s)
Cromosomas Humanos X , Genética de Población , Mutación INDEL , Polimorfismo Genético , Argentina , Femenino , Haplotipos , Humanos , Masculino , Reacción en Cadena de la Polimerasa Multiplex
7.
Homo ; 66(1): 44-59, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25435058

RESUMEN

Short tandem repeats (STRs) of the combined DNA index system (CODIS) are probably the most employed markers for human identification purposes. STR databases generated to interpret DNA profiles are also helpful for anthropological purposes. In this work, we report admixture, population structure, and genetic relationships of Mexican Mestizos with respect to Latin American and Caribbean populations based on 13 CODIS-STRs. In addition, new STR population data were included from Tijuana, Baja California (Northwest, Mexico), which represents an interesting case of elevated genetic flow as a bordering city with the USA. Inter-population analyses included CODIS-STR data from 11 Mexican Mestizo, 12 Latin American and four Caribbean populations, in addition to European, Amerindian, and African genetic pools as ancestral references. We report allele frequencies and statistical parameters of forensic interest (PD, PE, Het, PIC, typical PI), for 15 STRs in Tijuana, Baja California. This Mexican border city was peculiar by the increase of African ancestry, and by presenting three STRs in Hardy-Weinberg disequilibrium, probably explained by recurrent gene flow. The Amerindian ancestry in Central and Southeast of Mexico was the greatest in Latin America (50.9-68.6%), only comparable with the North of Central America and Ecuador (48.8-56.4%), whereas the European ancestry was prevalent in South America (66.7-75%). The African ancestry in Mexico was the smallest (2.2-6.3%) in Latin America (≥ 2.6%), particularly regarding Brazil (21%), Honduras (62%), and the Caribbean (43.2-65.2%). CODIS-STRs allowed detecting significant population structure in Latin America based on greater presence of European, Amerindian, and African ancestries in Central/South America, Mexican Mestizos, and the Caribbean, respectively.


Asunto(s)
Dermatoglifia del ADN , ADN/genética , Bases de Datos de Ácidos Nucleicos , Flujo Génico/genética , Indígenas Norteamericanos/genética , Repeticiones de Microsatélite/genética , Población Negra/genética , Región del Caribe , América Central , Frecuencia de los Genes/genética , Humanos , América Latina , México , América del Sur , Población Blanca/genética
8.
Pharmacogenomics J ; 14(6): 549-54, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24841973

RESUMEN

The prevalence of genetic polymorphisms identified as predictors of therapeutic-induced hepatitis C virus (HCV) clearance differs among ethnic groups. However, there is a paucity of information about their prevalence in South American populations, whose genetic background is highly admixed. Hence, single-nucleotide polymorphisms rs12979860, rs1127354 and rs7270101 were characterized in 1350 healthy individuals, and ethnicity was assessed in 259 randomly selected samples. The frequency of rs12979860CC, associated to HCV treatment response, and rs1127354nonCC, related to protection against hemolytic anemia, were significantly higher among individuals with maternal and paternal Non-native American haplogroups (64.5% and 24.2%), intermediate among admixed samples (44.1% and 20.4%) and the lowest for individuals with Native American ancestry (30.4% and 6.5%). This is the first systematic study focused on analyzing HCV predictors of antiviral response and ethnicity in South American populations. The characterization of these variants is critical to evaluate the risk-benefit of antiviral treatment according to the patient ancestry in admixed populations.


Asunto(s)
Antivirales/farmacología , Antivirales/uso terapéutico , Hepacivirus/efectos de los fármacos , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/genética , Polimorfismo de Nucleótido Simple/genética , Etnicidad/genética , Genotipo , Hepatitis C Crónica/virología , Humanos , Medición de Riesgo , América del Sur
9.
J Viral Hepat ; 15(11): 827-38, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18507755

RESUMEN

Previous studies have revealed that hepatitis B virus (HBV)/D and HBV/F predominate among blood donors from Buenos Aires, Argentina. In the present study, blood samples from two high-risk groups were analysed: 160 corresponding to street- and hospital-recruited injecting drug users [81.2% showing the 'anti-hepatitis B core antigen (anti-HBc) only' serological pattern] and 20 to hepatitis B surface antigen (HBsAg)(+)/anti-HBc(+) men who have sex with men. HBV genotypes were assigned by polymerase chain reaction amplification followed by restriction fragment length polymorphism and confirmed by nucleotide sequencing of two different coding regions. HBV DNA was detected in 27 injecting drug users (16.9%, occult infection prevalence: 7.7%), and 14 men who have sex with men (70%). HBV/A prevailed among injecting drug users (81.8%) while HBV/F was predominant among men who have sex with men (57.1%). The high predominance of HBV/A among injecting drug users is in sharp contrast to its low prevalence among blood donors (P = 0.0006) and men who have sex with men (P = 0.0137). Interestingly, all HBV/A S gene sequences obtained from street-recruited injecting drug users encoded the rare serotype ayw1 and failed to cluster within any of the known A subgenotypes. Moreover, one of the HBV strains from a hospital-recruited injecting drug user was fully sequenced and found to be the first completely characterized D/A recombinant genome from the American continent. Data suggest that two simultaneous and independent HBV epidemics took place in Buenos Aires: one spreading among injecting drug users and another one sexually transmitted among the homosexual and heterosexual population.


Asunto(s)
Consumidores de Drogas , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/genética , Hepatitis B/epidemiología , Homosexualidad Masculina , Abuso de Sustancias por Vía Intravenosa/complicaciones , Adulto , Argentina/epidemiología , Análisis por Conglomerados , ADN Viral/genética , Femenino , Genotipo , Virus de la Hepatitis B/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Filogenia , Reacción en Cadena de la Polimerasa/métodos , Polimorfismo de Longitud del Fragmento de Restricción , Prevalencia , Recombinación Genética , Análisis de Secuencia de ADN
10.
Forensic Sci Int ; 118(2-3): 131-5, 2001 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-11311825

RESUMEN

In the field of molecular diagnosis, forensic casework analysis is one of the most demanding investigations, due to its social impact. Optimization of DNA typing multiplex reactions with identical cycling conditions as those required by autosomal short tandem repeats (STR) multiplex reduces errors, and saves time and reagents. Previously, we validated a five Y-STRs set, all of them generating single band patterns. This work reports the optimization of combined multiplexes, a triplex (DYS19, DYS390 and DYS391) and a duplex (DYS392 and DYS393), that can be amplified in identical cycling conditions as those required by commercially available multiplex autosomal STR kits. In addition both Y chromosome multiplexes can be combined for co-injection on a capillary electrophoresis based automated sequencer. Statistical attributes of the haplotypes of the five Y-STR investigated were evaluated in unrelated males from different metropolitan areas of Argentina. This system was successfully used for investigating more than 350 forensic routine cases in our country.


Asunto(s)
Medicina Legal , Genética de Población , Secuencias Repetidas en Tándem/genética , Cromosoma Y/genética , Argentina , Bases de Datos Factuales , Haplotipos , Humanos , Masculino , Paternidad
11.
Am J Hum Genet ; 68(4): 990-1018, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11254455

RESUMEN

The genetic variance at seven Y-chromosomal microsatellite loci (or short tandem repeats [STRs]) was studied among 986 male individuals from 20 globally dispersed human populations. A total of 598 different haplotypes were observed, of which 437 (73.1%) were each found in a single male only. Population-specific haplotype-diversity values were.86-.99. Analyses of haplotype diversity and population-specific haplotypes revealed marked population-structure differences between more-isolated indigenous populations (e.g., Central African Pygmies or Greenland Inuit) and more-admixed populations (e.g., Europeans or Surinamese). Furthermore, male individuals from isolated indigenous populations shared haplotypes mainly with male individuals from their own population. By analysis of molecular variance, we found that 76.8% of the total genetic variance present among these male individuals could be attributed to genetic differences between male individuals who were members of the same population. Haplotype sharing between populations, phi(ST) statistics, and phylogenetic analysis identified close genetic affinities among European populations and among New Guinean populations. Our data illustrate that Y-chromosomal STR haplotypes are an ideal tool for the study of the genetic affinities between groups of male subjects and for detection of population structure.


Asunto(s)
Variación Genética/genética , Haplotipos/genética , Repeticiones de Microsatélite/genética , Filogenia , Cromosoma Y/genética , África , Alelos , Asia , Europa (Continente) , Evolución Molecular , Frecuencia de los Genes/genética , Pruebas Genéticas , Humanos , Masculino , Método de Montecarlo , Nueva Guinea , América del Sur
12.
Electrophoresis ; 20(8): 1733-9, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10435440

RESUMEN

The population of Argentina is mostly composed of people of European ancestry. Aboriginal communities are at present very reduced in number and restricted to small geographically isolated patches. Three aboriginal communities, the Mapuche, Tehuelche and Wichi, were selected for short tandem repeat (STR) investigation. The metropolitan population of the city of Buenos Aires was analyzed, with both micro- and minisatellites. The minisatellite loci D1S7, D2S44, D4S139, D5S110, D8S358, D10S28, and D17S26 were typed on HaeIII-digested DNA obtained from unrelated individuals. D1S80 was typed by polymerase chain reaction (PCR). The autosomal STRs THO1, FABP, D6S366, CSF1PO, TPOX, F13A1, FES/FPS, vWA, MBPA/B, D16S539, D7S820, D13S317, and RENA4 and the sex chromosome STRs HPRTB, DYS385, DYS3891, DYS38911, DYS19, DYS390, DYS391, DYS392, DYS393 and YCAII were also investigated. As a by-product of our investigations, a reference database was created that is routinely used in forensic casework and paternity testing. STR allele frequency distributions are characterized by significant differences within and also between different populations. In contrast, the minisatellite bin distribution of the metropolitan population is not significantly different from other Caucasian populations.


Asunto(s)
Antropología Física , Medicina Legal , Marcadores Genéticos , Alelos , Argentina , ADN/genética , Frecuencia de los Genes , Humanos , Indígenas Sudamericanos
13.
Hum Biol ; 70(5): 937-47, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9780520

RESUMEN

Eight STR systems (THO1, FABP, VWA, FES/FPS, HPRTB, F13A1, CSF1PO, and D6S366) were investigated in different ethnic groups of Argentina. Allele and genotype frequencies, power of exclusion, and discriminative power were investigated. Hardy-Weinberg expectations were calculated from heterozygosity levels. FST and G tests demonstrated that significant differences exist among the investigated populations for some of the eight STRs markers. The Wichi Indians are clearly separated from the Mapuche and Tehuelche, who in turn are closer to the European population, suggesting non-Amerindian admixture.


Asunto(s)
Etnicidad/genética , Frecuencia de los Genes , Polimorfismo Genético/genética , Secuencias Repetidas en Tándem , Argentina , Humanos , Indígenas Sudamericanos/genética , Población Blanca/genética
14.
Hum Biol ; 69(6): 777-83, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9353973

RESUMEN

VNTR loci provide a wealth of information for human genetic research, ranging from gene mapping to paternity testing and forensic identification. In this study we report the construction, validation, and analysis of the first local genetic database for VNTR markers for Argentina. A sample of the metropolitan population of Buenos Aires was typed by means of six VNTR systems. Allele frequencies and expected heterozygosity were calculated. The sample set was further tested for departures from Hardy-Weinberg equilibrium and power of exclusion. Allele frequency distributions are compatible with previously reported data on Caucasian populations, and no departures from Hardy-Weinberg equilibrium were detected.


Asunto(s)
Bases de Datos Factuales , Frecuencia de los Genes , Repeticiones de Minisatélite , Polimorfismo de Longitud del Fragmento de Restricción , Argentina , ADN/análisis , Humanos , Población Urbana , Población Blanca/genética
15.
Electrophoresis ; 18(9): 1608-12, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9378130

RESUMEN

DNA typing techniques are among the most advanced tools for human identification and can contribute to the identification of poorly preserved skeletal remains. Ten thousand people are thought to have been killed during the last dictatorship in Argentina (1976-1983) and there are few official records on the identity of the victims or the location of burials. A mass grave containing 340 skeletons was excavated using archeological methods. A small number of individuals was identified by traditional forensic methods and one family group by mitochondrial DNA (mtDNA) analysis. Due to the lack of antemortem physical information on many of the victims, the application of molecular methods is imperative to speed up the identification process. We have tested two molecular screening methods, Y chromosome-specific short tandem repeats (DYS19, DYS385, DYS389 I, DYS389 II, DYS390, DYS391, DYS392, DYS393) and amplification of autosomal microsatellites using nested primers. These methods can complement solely matrilineal mtDNA sequence data in the identification of "missing" persons.


Asunto(s)
Huesos/química , Dermatoglifia del ADN/métodos , Argentina , Secuencia de Bases , Crimen , ADN Mitocondrial/química , Femenino , Antropología Forense , Humanos , Masculino , Repeticiones de Minisatélite , Linaje , Cromosoma Y
16.
Electrophoresis ; 18(9): 1666-71, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9378142

RESUMEN

The evolutionary relationships of five Atlantic Aeglidae species (Aegla neuquensis affinis, A. humahuaca, A. jujuyana, A. platensis, and A. uruguayana) were studied by (i) satellite DNA analysis using a restriction enzyme digestion and hybridization pattern approach and (ii) genome screening by using randomly amplified polymorphic DNA (RAPD) typing. The identical restriction patterns and intense interspecific hybridization patterns obtained in this study strongly suggest a recent cladogenetic event for the Aeglidae. The species-specific amplification products which were detected using RAPD markers allowed species characterization. A total of 49 amplification products were used to construct trees by cluster analysis. The new scheme agrees in part with previous proposals based on biogeography and morphology. We considered that the subdivision northwestern-platensis species was probably due to the rising of the Andes, which started in the Middle Miocene. Divergence due to altitude is suggested by the different altitudinal distribution of three northwestern species along the same river. The possible role of selection by ecological factor/s was observed at the population level in A. jujuyana, which has a wider altitudinal range distribution. RAPD markers revealed a high level of intraspecific diversity and important genetic flow among populations. However, a few markers showed significant differences in frequency or H between the lowermost population and the other populations, located in a different biogeographical region. The differences were not in relation to geographical distance, and we interpreted them as being due to selection. Repetitive sequences constitute an important reservoir of genetic variation, and these results show their usefulness in testing and proposing evolutionary hypothesis in crabs. These sequences seem to have played an important role in aeglid evolution. Ecological factors related to altitude have probably influenced macro- and microevolutionary processes, at least in northwestern species.


Asunto(s)
Evolución Biológica , Crustáceos/genética , ADN/química , Secuencias Repetitivas de Ácidos Nucleicos , Animales , Argentina , Desoxirribonucleasa EcoRI/metabolismo , Desoxirribonucleasa HindIII/metabolismo , Desoxirribonucleasas de Localización Especificada Tipo II/metabolismo , Hibridación de Ácido Nucleico , Técnica del ADN Polimorfo Amplificado Aleatorio
17.
Electrophoresis ; 16(9): 1617-23, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8582344

RESUMEN

Human remains identification represents a challenging situation and constitutes a difficult task associated with mass disasters. The only highly efficient means for individual and family group reconstruction is that based on DNA typing. On July 18, 1994 an explosion destroyed the A.M.I.A. (Argentine Israeli Association). Over 100 people died; however, the exact number of victims is still being investigated. Our Service received over 70 remains to be characterized by DNA typing in order to determine the number of victims and to try to reconstruct the family groups to which they belonged. DNA was extracted by a cetyltrimethylammonium bromide (CTAB) based protocol, a rapid molecular screening of all samples was carried out by multiplex STR amplifications including HUMTH01, HUMFABP, HUMHPRTB, HUMRENA4, HUMVWA, HUMFES/FPS and Y27H39LR. Samples with identical genotypes were HaeIII-digested. Southern blotted and probed with YNH-24 (D2S44). PH-30 (D4S139). LH-1 (D5S110) and MS-1 (D1S7) for variable number of tandem repeats (VNTR) evaluation. The minisatellite variant repeat (MVR) approach was used in those cases in which band or profile shift were detected in Southern blot assays. Kinship between victims and putative relatives was initially evaluated by comparison of short tandem repeat (STR) profiles and then confirmed by VNTR with the above probes. The high identification efficiency attained in this case is, in part, supported by a previous experience, the DNA-based molecular characterization of human remains caused by the explosion of the Israeli Embassy in Buenos Aires, March 1992.


Asunto(s)
Explosiones , Pruebas Genéticas/métodos , Secuencias Repetitivas de Ácidos Nucleicos , Southern Blotting , Mapeo Cromosómico , ADN/genética , Antropología Forense , Genotipo , Humanos , Repeticiones de Minisatélite , Reacción en Cadena de la Polimerasa/métodos , Polimorfismo de Longitud del Fragmento de Restricción , Factores de Tiempo
18.
EXS ; 67: 211-9, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8400690

RESUMEN

DNA samples from 60 Mapuche Indians, representing 39 maternal lineages, were genetically characterized for (1) nucleotide sequences of the mtDNA control region; (2) presence or absence of a nine base duplication in mtDNA region V; (3) HLA loci DRB1 and DQA1; (4) variation at three nuclear genes with short tandem repeats; and (5) variation at the polymorphic marker D2S44. The genetic profile of the Mapuche population was compared to other Amerinds and to worldwide populations. Two highly polymorphic portions of the mtDNA control region, comprising 650 nucleotides, were amplified by the polymerase chain reaction (PCR) and directly sequenced. The 39 maternal lineages were defined by two or three generation families identified by the Mapuches. These 39 lineages included 19 different mtDNA sequences that could be grouped into four classes. The same classes of sequences appear in other Amerinds from North, Central, and South American populations separated by thousands of miles, suggesting that the origin of the mtDNA patterns predates the migration to the Americas. The mtDNA sequence similarity between Amerind populations suggests that the migration throughout the Americas occurred rapidly relative to the mtDNA mutation rate. HLA DRB1 alleles 1602 and 1402 were frequent among the Mapuches. These alleles also occur at high frequency among other Amerinds in North and South America, but not among Spanish, Chinese or African-American populations. The high frequency of these alleles throughout the Americas, and their specificity to the Americas, supports the hypothesis that Mapuches and other Amerind groups are closely related.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
ADN Mitocondrial/genética , Variación Genética , Indígenas Sudamericanos/genética , Alelos , Argentina , Secuencia de Bases , Dermatoglifia del ADN , Femenino , Frecuencia de los Genes , Marcadores Genéticos , Antígenos HLA-DQ/genética , Cadenas alfa de HLA-DQ , Antígenos HLA-DR/genética , Cadenas HLA-DRB1 , Antígenos de Histocompatibilidad Clase II/genética , Humanos , Masculino , Secuencias Repetitivas de Ácidos Nucleicos
19.
Mol Cell Endocrinol ; 84(1-2): R23-6, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1639210

RESUMEN

Polymerase chain reaction (PCR) amplification of nt 4502 to nt 5184 of the thyroglobulin (Tg) mRNA from several patients, with or without elevated serum thyrotropin (TSH), showed a predominant fragment of the expected size (683 bp) and a minor fragment of 512 bp. The sequence of this minor fragment revealed that 171 bp were missing between position 4567 and 4737. It is highly probable that the deleted sequence corresponds to a complete exon, suggesting an alternative splicing as mechanism for the generation of the minor transcript.


Asunto(s)
Bocio/genética , ARN Mensajero/genética , Tiroglobulina/genética , Secuencia de Aminoácidos , Secuencia de Bases , Bocio/metabolismo , Humanos , Datos de Secuencia Molecular , Mutación , Reacción en Cadena de la Polimerasa , Empalme del ARN , ARN Mensajero/biosíntesis , Transcripción Genética
20.
Thyroid ; 2(4): 321-4, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1493374

RESUMEN

Repeated sequences were identified in the 5' region of the human Tg gene in introns 4, 5, 10, and 11. Another repeated cluster was located in the 5' flanking sequences, approximately 6 Kb upstream from the first exon. The nucleotide sequence analysis indicated that these repeated sequences are members of the Alu family. The homology between the sequences of the intron 4 and the Alu consensus was 86%. The Alu member studied was oriented in the direction of transcription of the Tg.


Asunto(s)
Secuencias Repetitivas de Ácidos Nucleicos , Tiroglobulina/genética , Secuencia de Bases , Southern Blotting , ADN/química , Desoxirribonucleasa EcoRI , Exones , Humanos , Intrones , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico , Mapeo Restrictivo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA