Two Sets of DNA, One Body: A Multidisciplinary Review of Human Chimerism from Biological Mechanisms to Clinical and Forensic Challenges
DOI:
https://doi.org/10.51173/ijmhs.v3i1.80Keywords:
Vanishing Twin Syndrome, Next-Generation Sequencing (NGS), Forensic DNA, Micro Chimerism, Human ChimerismAbstract
Background: One person, one genome; this is the foundation of the biological axiom, nowadays it is exposed to a big challenge due to the human chimerism phenomenon. The appearance of genetically distinct lineages in one person. It was rare in the past, but nowadays it has become more common due to Multifactorial causes. In this narrative review, we will expose a different aspect and different Implications of these phenomena.
Methods: We adopted a narrative approach to collect the newest studies and reports published between 2018 and 2026, related to this phenomenon. The data were collected and analysed from 18 article review, from academic data base (PubMed, NCBI).
Results: The review revealed that there is a comprehensive shift in these couple of years, 2025-2026, where the chimerism has evolved from a diagnostic complication into a therapeutic tool to achieve the immunological tolerance in organ transplantation and bioengineering human organs within interspecies hosts, which triggered to create a gap in the forensic aspect, due to the limitation in the traditional (STR-PCR) test which failed to account for genomic plurality and that led to legal paradoxes in parentage and criminal identification.
Conclusion: The science and forensic fields have to standardise all concepts and protocols about the chimerism, which include the medical terms and the procedures of collecting samples and tissue from the body and using advanced DNA technologies like NGS. We have to accept that biological identity is not always a single profile or a static code; instead, it can be a complex and changing mosaic.
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