Molecular Biology Reports

, Volume 38, Issue 6, pp 4003–4006 | Cite as

Eyes wide open: the (mis)use of combined power of discrimination for X-linked short tandem repeats

  • Enrique Medina-Acosta
  • Filipe Brum Machado

In the field of Genetic Epidemiology it is well established that ignoring interallelic multipoint gametic disequilibrium (GD) introduces false-positive evidence of linkage for sib-pair (kinship) analysis, especially in cases of sample deficiencies [1]. In the field of Forensic Genetics this proven concept is, in stark contrast, largely trivialized or ignored. There is an alarming accrual of forensic reports (Online Resource 1) announcing population data on short tandem repeats loci mapping on X chromosome (X-STRs) in which the product rule is applied to syntenic loci (i.e., being located on the same chromosome whether or not there is demonstrable genetic linkage between them), mostly ignoring the second law of Mendelian inheritance, and fundamental notions on genetic linkage status. We believe that the issue has been utterly disregarded, and thus it can no longer go unnoticed without opinion.

We center our opinion at the most crucial aspect that underlies meaningful calculation of...


Short Tandem Repeat Product Rule Short Tandem Repeat Locus Gametic Disequilibrium Tandem Repeat Locus 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Supplementary material

11033_2010_518_MOESM1_ESM.doc (36 kb)
ESM_1 List (chronological order) of research articles in the field of Forensic Genetics reporting combined power of discrimination (CPD) values using syntenic tetrameric and pentameric microsatellite loci on human X chromosome (X-STRs). The list was generated using the EndNote (Thomson Reuters) reference manager software and an internet connection to PubMed through July 24th, 2010 (DOC 36 kb)
11033_2010_518_MOESM2_ESM.doc (151 kb)
ESM_2 The complete list of marker systems used in the ten studies from which Combined Power of Discrimination (CPD) values were taken to calculate combined match probability (CMP) values plotted in Fig. 1 (main typescript) (DOC 151 kb)


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Copyright information

© Springer Science+Business Media B.V. 2010

Authors and Affiliations

  1. 1.Núcleo de Diagnóstico e Investigação MolecularUniversidade Estadual do Norte Fluminense Darcy RibeiroCampos dos GoytacazesBrazil
  2. 2.Departamento de Genética, Faculdade de Medicina de Ribeirão PretoUniversidade de São PauloRibeirão PretoBrazil
  3. 3.Laboratório de Biotecnologia, Centro de Biociências e BiotecnologiaUniversidade Estadual do Norte Fluminense Darcy RibeiroCampos dos GoytacazesBrazil

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