The Kerala government is exploring the use of advanced next-generation DNA sequencing technology to aid in the identification of 52 decomposed samples of the Wayanad landslides victims.
An identification process is under way at the Regional Forensic Lab in Kannur. A six-member team has been working tirelessly to identify the victims, but the lack of clean DNA, particularly from decayed samples, has hindered the process.
Revenue Minister K. Rajan stated that the government had initiated talks to utilise next-generation sequencing (NGS) to identify samples where extraction of clean DNA had been difficult. “We want to leverage every possible technology to identify the victims and have held discussions with experts in the field to explore the possibility of identification from putrefied samples,” he said.
NGS facilities are available at Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, and ICMR-National Institute of Virology field unit in Alappuzha. Unlike traditional short tandem repeat (STR) analysis, NGS is faster and more accurate, providing a comprehensive view of the human genome and simultaneous sequencing of DNA fragments. It also requires lower sample input, making it a promising solution for identifying decomposed samples.
The forensic lab team has been working non-stop to build profiles from over 442 samples in the past two weeks. While the gender of 248 samples has been identified, the team has established identity (with names) by cross-matching with reference samples in 42 cases. Bone samples have aided identification in such cases. Fifty-four samples were profiled from 154 body parts.
Cross-matching
Mr. Rajan said that cross-matching would begin for 118 missing persons with the DNA profile built from 401 samples. “Ninety-one blood samples of relatives are available for cross-matching. In three cases, close relatives will arrive from other States for sample collection,” he said. “However, cross-matching also poses challenges in cases where close relatives are also deceased, and samples of spouses have been collected instead of that of father/mother. Such cases require fresh sample collection for accurate cross-matching with DNA profiles.”
