Sudden arrhythmic death syndrome (SADS) is a major cause of unexplained sudden death in young individuals and may require retrospective forensic genetic investigation to assess familial risk. However, biological material from the deceased is not always available due to immediate burial, cultural or religious considerations. In such cases, forensic genetic analysis of alternative DNA sources may provide valuable information. A male in his early twenties died suddenly in his sleep under unexplained circumstances. Autopsy findings were consistent with SADS. Due to family grief and religious beliefs, the individual was buried shortly after death, preventing collection of biological samples for genetic testing. One year later, the family requested evaluation of cardiac risk for the surviving sibling. DNA from family members was enriched using a 72-gene cardiac panel and sequenced using a next-generation sequencing (NGS) platform. Analysis identified single nucleotide variants (SNVs) with potentially damaging effects in both parents, with the surviving son inheriting variants that could be clinically significant. To determine whether the deceased carried the same variants, alleged personal items belonging to the deceased were submitted for forensic DNA analysis together with buccal swabs from family members. Six items were screened using STR profiling to establish ownership. Kinship analysis comparing STR profiles from the items with those of the biological parents and sibling supported that DNA recovered from one leather bracelet originated from the deceased individual. DNA quantification indicated ultra-low DNA input (2 pg/µl), highlighting challenges associated with forensic low-template DNA. To screen for the four identified SNVs, short amplicons (~100 bp) were designed for degraded, low-template forensic DNA. Illumina TruSeq adapter overhangs were incorporated into the primer design, enabling a streamlined two-step PCR workflow that minimized sample handling and DNA loss while generating sequencing-ready libraries. Despite limited DNA input, robust amplification and sequencing were achieved, with mean coverage exceeding 500× across target loci, demonstrating feasibility of targeted variant detection from challenging forensic samples. Analysis indicated that the variant combination observed in the deceased differed from that detected in the surviving sibling and was unlikely to explain the cause of death. However, the surviving brother should remain under medical surveillance, as the identified variants may still be clinically significant. This study demonstrates the feasibility of a cost-effective forensic genetic approach for postmortem variant screening from minute DNA recovered from personal belongings, providing an alternative to exhumation and highlighting the expanding role of forensic genetics in medico-legal and familial risk investigations.

Authors

• Kyriakos Tsangaras (Cyprus Institute of Neurology and Genetics, Cyprus)
• Panayiotis Manoli (Cyprus Institute of Neurology and Genetics, Cyprus)
• Giorgos Iosif (Cyprus Institute of Neurology and Genetics, Cyprus)
• Vaso Stribley (Cyprus Institute of Neurology and Genetics, Cyprus)
• Kyriakos Mylonas (Cyprus Institute of Neurology and Genetics, Cyprus)
• Marios Cariolou (Cyprus Institute of Neurology and Genetics, Cyprus)
• Stavroulla Xenophontos (Cyprus Institute of Neurology and Genetics, Cyprus)