2006 GEP-ISFG collaborative exercise on mtDNA: reflections about interpretation, artefacts, and DNA mixtures

Received 26 July 2007; received in revised form 11 September 2007; accepted 2 October 2007.

Abstract

We report the results of the seventh edition of the GEP-ISFG mitochondrial DNA (mtDNA) collaborative exercise. The samples submitted to the participant laboratories were blood stains from a maternity case and simulated forensic samples, including a case of mixture. The success rate for the blood stains was moderate (∼77%); even though four inexperienced laboratories concentrated about one-third of the total errors. A similar success was obtained for the analysis of mixed samples (78.8% for a hair–saliva mixture and 69.2% for a saliva–saliva mixture). Two laboratories also dissected the haplotypes contributing to the saliva–saliva mixture. Most of the errors were due to reading problems and misinterpretation of electropherograms, demonstrating once more that the lack of a solid devised experimental approach is the main cause of error in mtDNA testing.

Keywords: mtDNA, Mixture, Recommendations: Phylogeny, GEP-ISFG, Collaborative exercise

a Comisaría General de Policía Científica, DNA Laboratory, Madrid, Spain

b Instituto Nacional de Toxicología y Ciencias Forenses, Departamento de Madrid, Spain

c Instituto de Patología e Inmunología Molecular IPATIMUP, Universidade do Porto, Portugal

d Instituto Nacional de Toxicología y Ciencias Forenses, Departamento de Barcelona, Spain

e Lab. Genètica, Ins. Universitari d’Investigacions en C.C. de la Salut i Dep. de Biol., Universitat Illes Balears, Spain

f Laboratorio de Genética Humana, Universidade da Madeira, Portugal

g Fundación Ins. de Estudios Avanzados, C. Biotecnología, U. Pol. Genéticos, Caracas, Venezuela

h Genomic Engenharia Molecular LTDA, Sao Paulo, Brazil

i Serviço de Genética e Biologia Forense, Inst. Nacional de Med. Legal, Delegação do Centro, Portugal

j Istituto di Medicina Legale e delle Assicurazioni, Università Cattolica del S. Cuore, Rome, Italy

k Neodiagnóstica, Lleida, Spain

l Unidade de Xenética, Ins. de Medicina Legal, Universidade de Santiago de Compostela, Galicia, Spain

m Banco de ADN, Universidad del País Vasco, Vitoria-Gasteiz, Spain

n Laboratorio de Investigaçáo de Paternidade, Universidade Estadual Paulista – UNESP, Sao Paulo, Brazil

o Unitat de Biologia Evolutiva, Universitat Pompeu Fabra, Barcelona, Spain

p Servicio de Huellas Digitales Genéticas, Fac. Farmacia y Bioquímica, Universidad de Buenos Aires, Argentina

q Laboratoire D́Hématologie, Bordeaux, France

r Serviço de Genética e Biologia Forense, Inst. Nacional de Medicina Legal, Delegação do Sul, Portugal

s DataGene, Parque Tecnológico de Derio, Bizkaia, Spain

t Banco Nacional de Datos Genéticos, Buenos Aires, Argentina

u ADF TecnoGen, Madrid, Spain

v Dirección General de la Guardia Civil, Madrid, Spain

w Instituto Nacional de Toxicología y Ciencias Forenses, Delegación de Canarias, La Laguna, Spain

x Laboratorio de Pericias, Instituto Geral de Pericias, Porto Alegre, Brazil

y Laboratorio de DNA, Inst. Nacional de Med. Legal y C.C. Forenses, Santafé de Bogotá, Colombia

z Departamento de Medicina Legal y Forense, Facultad de Medicina, Universidad Complutense, Madrid, Spain

a1 Instituto Nacional de Toxicología y Ciencias Forenses, Departamento de Sevilla, Spain

a2 Laboratorio de Identificación Genética, Dpto. de Medicina Legal, Universidad de Granada, Spain

a3 Instituto de Genética Médica, Hospital Italiano, Montevideo, Uruguay

a4 Centro de Análisis Genéticos C.A.G.T., Zaragoza, Spain

a5 Laboratorio Biológico, Dirección Nacional de Policía Técnica, Montevideo, Uruguay

a6 Laboratorio de Genética, Instituto Anatómico Forense, Las Palmas, Spain

a7 Laboratorio de Genética Clínica LabGenetics, Madrid, Spain

a8 PRICAI -Fundación Favaloro, Buenos Aires, Argentina

a9 Unidad de Genética Forense, Sección de Bioquímica, Dep. de Ciencias Forenses, Heredia, Costa Rica

a10 Serviço de Genética e Biologia Forense, Inst. Nacional de Med. Legal, Delegação do Norte, Portugal

a11 Lab. de Identificación Genética, Ins. Multidisciplinario de Biol. Celular (IMBICE), La Plata, Argentina

a12 Laboratorio de Inmunogenética y Diagnostico Molecular, Córdoba, Argentina

Corresponding author.

PII: S1872-4973(07)00173-1

doi:10.1016/j.fsigen.2007.10.010

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