Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Forensic Sci ; 46(3): 647-60, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11373004

RESUMO

The amplification and typing conditions for the 13 core CODIS loci and their forensic applicability were evaluated. These loci are CSF1PO, FGA, TH01, TPOX, vWA, D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51, and D21S11. Results were obtained using the multiplex STR systems AmpFlSTR Profiler Plus and AmpFlSTR COfiler (Applied Biosystems, Foster City, CA), GenePrint PowerPlex (Promega Corporation, Madison, WI), and subsets of these kits. For detection of fluorescently labeled amplified products, the ABI Prism 310 Genetic Analyzer, the ABI Prism 377 DNA Sequencer, the FMBIO II Fluorescent Imaging Device, and the Fluorlmager were utilized. The following studies were conducted: (a) evaluation of PCR parameter ranges required for adequate performance in multiplex amplification of STR loci, (b) determination of the sensitivity of detection of the systems, (c) characterization of non-allelic PCR products, (d) evaluation of heterozygous peak intensities, (e) determination of the relative level of stutter per locus, (f) determination of stochastic PCR thresholds, (g) analysis of previously typed case samples, environmentally insulted samples, and body fluid samples deposited on various substrates, and (h) detection of components of mixed DNA samples. The data demonstrate that the commercially available multiplex kits can be used to amplify and type STR loci successfully from DNA derived from human biological specimens. There was no evidence of false positive or false negative results and no substantial evidence of preferential amplification within a locus. Although at times general balance among loci labeled with the same fluorophore was not observed, the results obtained were still valid and robust. Suggested criteria are provided for determining whether a sample is derived from a single source or from more than one contributor. These criteria entail the following: (a) the number of peaks at a locus, (b) the relative height of stutter products, and (c) peak height ratios. Stochastic threshold levels and the efficiency of non-templated nucleotide addition should be considered when evaluating the presence of mixtures or low quantity DNA samples. Guidelines, not standards, for interpretation should be developed to interpret STR profiles in cases, because there will be instances in which the standards may not apply. These instances include (a) a primer binding site variant for one allele at a given locus, (b) unusually high stutter product, (c) gene duplication, and (d) translocation.


Assuntos
Impressões Digitais de DNA/métodos , Reação em Cadeia da Polimerase/métodos , Sequências de Repetição em Tandem/genética , Medicina Legal/métodos , Amplificação de Genes , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Manejo de Espécimes , Espectrometria de Fluorescência
2.
Electrophoresis ; 19(1): 94-100, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9511869

RESUMO

A series of experiments was performed to analyze the utility of capillary electrophoresis (CE) with multiwavelength detection capabilities for multiplex typing of short tandem repeat loci. Characteristics of the sieving polymer, hydroxyethylcellulose, which affect resolution of single strand (ss) DNA fragments were examined. Additionally, the effects of denaturant in the polymer system, separation voltage, and analysis temperature were studied to ascertain their effects on DNA separations and capillary lifetime. The use of elevated run temperature (60 degrees C) was found to improve sizing precision, to increase the lifetime of capillaries (100 runs or more per capillary), and to provide runtimes of under 20 min. Finally, 100 individual human DNA samples were typed successfully using CE. The average resolution obtained was 1.4 bases for a 200 base fragment with a standard deviation of sizing of 0.2 bases, allowing all alleles examined to be distinguished clearly.


Assuntos
Eletroforese Capilar/métodos , Sequências Repetitivas de Ácido Nucleico , DNA de Cadeia Simples/química , DNA de Cadeia Simples/isolamento & purificação , Humanos , Desnaturação de Ácido Nucleico , Espectrometria de Fluorescência
3.
J Forensic Sci ; 42(5): 846-9, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9304831

RESUMO

Allele frequencies for three tetrameric short tandem repeat (STR) loci HUMTHO1, TPOX, and CSF1PO and a variable number tandem repeat locus D1S80 were determined in United States Caucasian, African American, and Hispanic sample populations. All loci, except the TPOX locus in the Caucasian sample population, meet Hardy-Weinberg expectations. There is no evidence for association of alleles among the four loci. The allelic frequency data are similar to other comparable data within the same major population group.


Assuntos
População Negra/genética , DNA/análise , Antropologia Forense , Genética Populacional , Repetições Minissatélites , População Branca/genética , Frequência do Gene , Hispânico ou Latino/genética , Humanos , Estados Unidos
4.
J Forensic Sci ; 42(4): 701-7, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9243836

RESUMO

Studies were performed to define the typing conditions and evaluate the forensic applicability of multiplex amplification of three STR loci, CSF1PO, TPOX, and THO1. Results were obtained using the GenePrint STR System (Promega Corporation, Madison, WI) Kit. To determine the utility of the GenePrint STR System for forensic casework analyses, the following experiments were conducted: 1) analysis of mixed body fluid; 2) determination of the sensitivity of detection; and 3) evaluation of results from biological samples from casework. In addition, the following simulated forensic conditions were assayed to detect whether or not there may be adverse effects on the ability to type these loci: 1) chemical contaminant effects on the DNA in body fluid samples; 2) the effects on DNA from samples deposited on various substrates; 3) the consequences of micro-organism contamination; and 4) the effect of sunlight and storage conditions on the integrity of the STR profiles/DNA. The data demonstrate that STR typing of biological samples exposed to a variety of environmental insults yields reliable results and that the analysis of the STR loci CSF1PO, TPOX, and THO1 can be applied in a forensic setting.


Assuntos
Medicina Legal/métodos , Sequências Repetitivas de Ácido Nucleico , Alelos , Animais , Líquidos Corporais/química , Poluentes Ambientais/toxicidade , Feminino , Corantes Fluorescentes , Humanos , Masculino , Repetições de Microssatélites , Reação em Cadeia da Polimerase/métodos , Kit de Reagentes para Diagnóstico , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Coloração pela Prata
5.
Forensic Sci Int ; 90(3): 215-21, 1997 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-9493337

RESUMO

Allele frequencies for six tetrameric short tandem repeat (STR) loci CSF1PO, TPOX, THO1, D3S1358, VWA, and FGA were determined in a Black African sample population from Zimbabwe. All loci are highly polymorphic and meet Hardy-Weinberg expectations. An inter-class correlation test analysis detected only one departure from independence out of 15 pair-wise comparisons of the six loci (i.e., CSF1PO/VWA loci, P = 0.026). The allele frequency data at four of the six STR loci in the Black African sample population are similar to African American data.


Assuntos
População Negra/genética , DNA/análise , Marcadores Genéticos/genética , Sequências Repetitivas de Ácido Nucleico/genética , Alelos , Impressões Digitais de DNA , Primers do DNA/química , Ligação Genética/genética , Humanos , Reação em Cadeia da Polimerase , Polimorfismo Genético/genética , Estados Unidos , Zimbábue
6.
Forensic Sci Int ; 83(3): 229-35, 1996 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-9032956

RESUMO

Allele frequencies for six tetrameric short tandem repeat (STR) loci CSF1PO, TPOX, THO1, D3S1358, VWA and FGA were determined in a Caucasian population sample from Portugal. All loci are highly polymorphic and meet Hardy-Weinberg expectations. There is little evidence for association of alleles among the six loci. The three loci D3S1358, VWA and FGA are more polymorphic and, hence, are more informative than the loci CSF1PO, TPOX, and THO1. However, all six loci would be useful for human identification applications. The STR allelic frequency data are similar to other Caucasian data.


Assuntos
Sequências Repetitivas de Ácido Nucleico/genética , Alelos , Bases de Dados Factuais , Humanos , Reação em Cadeia da Polimerase , Vigilância da População/métodos , Portugal , População Branca
7.
J Forensic Sci ; 40(4): 536-45, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7595290

RESUMO

The reliability of a D1S80 typing procedure has been evaluated using simulated forensic specimens. D1S80 alleles were detectable in DNA recovered from bloodstains exposed to sunlight for up to 20 weeks. However, D1S80 alleles were undetectable in semen stains after six weeks sunlight exposure. Analysis of blood and semen that had been deposited on a variety of substrates and examined over a twenty-week period, revealed no systematic influence of substrate on the ability to type D1S80. A study in which body fluids were exposed to household chemical substances, such as bleach, acids, oil, and gasoline, indicated that only HCl and bleach had a deleterious effect on the ability to type D1S80. In addition, personal care chemical products were without effect on D1S80 allele patterns derived from semen. Exposure of blood and semen to four different species of microorganisms resulted in no alteration of D1S80 genotype patterns in these body fluids. D1S80 genotypes could be reliably determined even when body fluids from different individuals were mixed. DNA from no animals other than humans and higher primates could be amplified at locus D1S80 when the DNA had been isolated through an organic procedure. These studies, in concert with the reports of others, indicate that the procedures for the amplification and detection of genetic variation at locus D1S80 are suitable for use on forensic evidentiary materials.


Assuntos
Alelos , DNA/análise , DNA/sangue , Saliva/química , Sêmen/química , Animais , Bactérias , Feminino , Medicina Legal , Humanos , Masculino , Reação em Cadeia da Polimerase , Solo , Luz Solar , Esfregaço Vaginal
8.
J Forensic Sci ; 40(1): 38-44, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7876800

RESUMO

Allele frequencies for the locus D1S80 were determined in African American, Caucasian, Southeastern Hispanic, Southwestern Hispanic, and Oriental sample populations using the polymerase chain reaction and subsequent electrophoresis and silver staining of the amplified products. Due to the presence of anodal and cathodal electrophoretic variants (in reference to the steps in an allelic ladder), allele frequencies were established using a classification protocol based on the steps in the allelic ladder. All sample populations met Hardy-Weinberg expectations for D1S80. In addition, there was no evidence for association of alleles between the loci D1S80 and D1S7. The product of allele frequencies from the data from the sample populations in this study can be used in forensic analyses and paternity tests to estimate the frequency of a D1S80 DNA genotype.


Assuntos
Asiático/genética , População Negra/genética , DNA/genética , Medicina Legal , Marcadores Genéticos/genética , Hispânico ou Latino/genética , Repetições Minissatélites , População Branca/genética , Alelos , Manchas de Sangue , Mapeamento Cromossômico , Eletroforese em Gel de Poliacrilamida , Frequência do Gene , Humanos , Polimorfismo de Fragmento de Restrição
9.
J Forensic Sci ; 38(5): 1176-82, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8228885

RESUMO

The interlaboratory typing of DNA specimens that have been amplified at the D1S80 locus necessitates the use of a standard allelic reference ladder. This communication describes a technique in which individual, amplified alleles are isolated, combined, and amplified by PCR to produce a functional reference ladder composed of many of the alleles that occur at this locus. The amplified ladder can serve directly as a template source for production of the next generation of reference ladder. This process, in which each amplified ladder serves as the template for the next has been carried through multiple generations.


Assuntos
Alelos , Amplificação de Genes , Mapeamento Cromossômico , Impressões Digitais de DNA/métodos , Humanos , Reação em Cadeia da Polimerase , Valores de Referência , Sequências Repetitivas de Ácido Nucleico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...