Evidence of partial and weak gametic disequilibrium across clusters of pericentromeric short tandem repeats loci on human X chromosome: Proceed with caution in forensic genetics

Abstract Forensic genetics represents a combination of molecular and population genetics. Personal identification and kinship analysis (e.g. paternity testing) are the two main subjects of forensic DNA analysis. Biological specimens from which DNA is isolated are blood, semen, saliva, tissues, bones, teeth, hairs. Genotyping has become a basis in the characterization of forensic biological evidence. It is performed using a variety of genetic markers, which are divided into two large groups: bi-allelic (single-nucleotide polymorphisms, SNP) and multi-allelic polymorphisms (variable number of tandem repeats, VNTR and short tandem repeats, STR). This review describes the purpose of genetic markers in forensic investigation and their limitations. The STR loci are currently the most informative genetic markers for identity testing, but in cases without a suspect SNP can predict offender’s ancestry and phenotype traits such as skin, eyes and hair color. Nowadays, many countries worldwide have established forensic DNA databases based on autosomal short tandem repeats and other markers. In order for DNA profile database to be useful at a national or international level, it is essential to standardize genetic markers used in laboratories.

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Animal Forensic Genetics

Genes ◽

10.3390/genes12040515 ◽

2021 ◽

Vol 12 (4) ◽

pp. 515

Author(s):

Adrian Linacre

Keyword(s):

Short Tandem Repeats ◽

Tandem Repeats ◽

Potential Role ◽

Forensic Genetics ◽

Human Species ◽

Domestic Species ◽

Traditional Medicines ◽

Increased Sensitivity ◽

Forensic Testing ◽

Short Tandem

Animal forensic genetics, where the focus is on non-human species, is broadly divided in two: domestic species and wildlife. When traces of a domestic species are relevant to a forensic investigation the question of species identification is less important, as the material comes from either a dog or a cat for instance, but more relevant may be the identification of the actual pet. Identification of a specific animal draws on similar methods to those used in human identification by using microsatellite markers. The use of cat short tandem repeats to link a cat hair to a particular cat paved the way for similar identification of dogs. Wildlife forensic science is becoming accepted as a recognised discipline. There is growing acceptance that the illegal trade in wildlife is having devasting effects on the numbers of iconic species. Loci on the mitochondrial genome are used to identify the most likely species present. Sequencing the whole locus may not be needed if specific bases can be targeted. There can be benefits of increased sensitivity using mitochondrial loci for species testing, but occasionally there is an issue if hybrids are present. The use of massively parallel DNA sequencing has a role in the identification of the ingredients of traditional medicines where studies found protected species to be present, and a potential role in future species assignments. Non-human animal forensic testing can play a key role in investigations provided that it is performed to the same standards as all other DNA profiling processes.

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D18S535, D1S1656 and D10S2325: three efficient short tandem repeats for forensic genetics

International Journal of Legal Medicine ◽

10.1007/pl00007705 ◽

1999 ◽

Vol 112 (6) ◽

pp. 360-363 ◽

Cited By ~ 17

Author(s):

P. Wiegand ◽

M. V. Lareu ◽

M. Schürenkamp ◽

M. Kleiber ◽

B. Brinkmann

Keyword(s):

Short Tandem Repeats ◽

Tandem Repeats ◽

Forensic Genetics ◽

Short Tandem

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Five X-chromosome short tandem repeats in a Western Mexican population

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm.2008.279 ◽

2008 ◽

Vol 46 (10) ◽

Author(s):

Yeminia Valle ◽

Jorge Ramón Padilla-Gutiérrez ◽

Katya Rodarte ◽

Antonio Quintero-Ramos ◽

Rocío Ortiz ◽

...

Keyword(s):

X Chromosome ◽

Short Tandem Repeats ◽

Tandem Repeats ◽

Mexican Population ◽

Short Tandem

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Forensic efficiency estimate and phylogenetic analysis for Chinese Kyrgyz ethnic group revealed by a panel of 21 short tandem repeats

Royal Society Open Science ◽

10.1098/rsos.172089 ◽

2018 ◽

Vol 5 (6) ◽

pp. 172089 ◽

Cited By ~ 6

Author(s):

Yuxin Guo ◽

Chong Chen ◽

Tong Xie ◽

Wei Cui ◽

Haotian Meng ◽

...

Keyword(s):

Ethnic Group ◽

Phylogenetic Trees ◽

Short Tandem Repeats ◽

Tandem Repeats ◽

Forensic Genetics ◽

Genetic Relationships ◽

Individual Identification ◽

Forensic Sciences ◽

Dna Index ◽

Short Tandem

Short tandem repeats (STRs) with a high level of polymorphisms and convenient detection method play an indispensable role in human population and forensic genetics. Recently, we detected the 21 autosomal non-combined DNA index system (non-CODIS) STR loci in a Kyrgyz ethnic group, calculated their forensic parameters and analysed its genetic relationships with reference populations from China. In total, 168 alleles were observed at 21 non-CODIS STRs with corresponding allelic frequencies from 0.0016 to 0.4788. No significant deviations at these STRs were observed from the Hardy–Weinberg equilibrium. The values of cumulative power of discrimination and probability of exclusion for all the 21 non-CODIS STRs were 0.99999999999999999998835 and 0.9999994002, respectively. Furthermore, the analyses of phylogenetic trees, genetic distances and interpopulation differentiations demonstrated that the Kyrgyz group had relatively close genetic relationships with the Uygur and Kazak groups. These 21 non-CODIS STRs were characterized by high genetic diversities in the Kyrgyz group and could be applied as a robust tool for individual identification and kinship testing in forensic sciences.

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