International Journal of Legal Medicine

, Volume 132, Issue 5, pp 1281–1285 | Cite as

The forensic value of X-linked markers in mixed-male DNA analysis

  • HaiJun He
  • Lagabaiyila Zha
  • JinHong Cai
  • Jian HuangEmail author
Short Communication


Autosomal genetic markers and Y chromosome markers have been widely applied in analysis of mixed stains at crime scenes by forensic scientists. However, true genotype combinations are often difficult to distinguish using autosomal markers when similar amounts of DNA are contributed by multiple donors. In addition, specific individuals cannot be determined by Y chromosomal markers because male relatives share the same Y chromosome. X-linked markers, possessing characteristics somewhere intermediate between autosomes and the Y chromosome, are less universally applied in criminal casework. In this paper, X markers are proposed to apply to male mixtures because their true genes can be more easily and accurately recognized than the decision of the genotypes of AS markers. In this study, an actual two-man mixed stain from a forensic case file and simulated male-mixed DNA were examined simultaneously with the X markers and autosomal markers. Finally, the actual mixture was separated successfully by the X markers, although it was unresolved by AS-STRs, and the separation ratio of the simulated mixture was much higher using Chr X tools than with AS methods. We believe X-linked markers provide significant advantages in individual discrimination of male mixtures that should be further applied to forensic work.


Male mixtures Likelihood ratios Separation accuracy Similar amounts of DNA X-linked markers Forensic genetics 

Supplementary material

414_2018_1841_MOESM1_ESM.docx (15 kb)
ESM 1 (DOCX 15 kb)


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Forensic Pathology, College of Forensic Medicine, Xi’an Jiaotong UniversityXi’anPeople’s Republic of China
  2. 2.Criminal Investigation Division, Changsha Public Security BureausChangshaPeople’s Republic of China
  3. 3.Department of Forensic Sciences, School of Basic MedicineCentral South UniversityChangshaPeople’s Republic of China
  4. 4.Department of Forensic Genetics, Brain Hospital of Hunan ProvinceHunan University of Chinese MedicineChangshaPeople’s Republic of China

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