Cracking Crimes with DNA, Microbes, and Insects: Inside the Evolving World of Forensic Science.

Modern forensic science has evolved far beyond what is portrayed in popular crime dramas. While DNA testing remains a cornerstone in criminal investigations, researchers are increasingly turning to the natural world—microbes, insects, and even moths—to decode the hidden timeline of death and support justice in unprecedented ways.

DNA analysis has revolutionized the process of identifying both suspects and victims. Through the examination of genetic markers, forensic scientists are able to determine identities with striking precision. From solving cold cases and tracking down serial offenders to verifying royal bloodlines, DNA profiling has become an indispensable tool. As John Butler, a forensic scientist at the National Institute of Standards and Technology, explains, “There's a lot more nuances with DNA testing than people appreciate.” Environmental sampling is now enhancing this process, offering investigators a more comprehensive view of the traces individuals leave behind.

But forensic inquiry does not stop at DNA. At the Southeast Texas Applied Forensic Science Facility, entomologist Sibyl Bucheli studies how insects and microbial life interact with decomposing human remains. In a striking case, her team analyzed a human scalp colonized by case-making clothes moth caterpillars, which had spun silk shelters from the victim's hair. By extracting mitochondrial DNA from this unusual source, they provided valuable insights into the identity of the deceased. Rather than offering a static snapshot, such biological evidence captures the unfolding story of human decomposition—one that can help determine time of death with increasing accuracy.

Microbial analysis is proving especially promising in this regard. Jessica Metcalf, a microbiologist at Colorado State University, studies how microbial communities change during decomposition. Her research found consistent microbial succession patterns across various U.S. environments, even linking microbial populations to the insects that frequent decomposing bodies. “If you're a microbe looking to decay flesh, riding along on insects that lay their eggs on decaying flesh is probably a pretty good plan,” she noted. These findings have led to the development of microbial “clocks,” which may become essential tools for estimating postmortem intervals.

Forensic science also has the power to bridge seemingly unrelated fields, such as religion and biology. Sister Marija Krucifiksa Kozulić, a Croatian nun celebrated for her charitable work, became the subject of a canonization investigation nearly 100 years after her death. Locating and verifying her remains required extensive scientific effort. Forensic scientist Mitchell Holland, along with a Croatian-American team, used DNA testing to confirm her identity—a process that took nearly a decade and exemplified the collaboration between science and spiritual tradition.

On the technological front, forensic laboratories continue to refine DNA profiling methods. At Promega Corporation, biochemist Bob McLaren and his colleagues have tackled a persistent challenge in forensic DNA testing: “stutter” artifacts. These misleading fragments arise during the amplification of short tandem repeats via polymerase chain reaction (PCR). The team’s breakthrough came in the form of a new DNA polymerase that significantly reduces these artifacts, improving the accuracy of DNA readings—particularly when samples contain genetic material from multiple individuals.

For professionals like Colby Duncan, a forensic scientist working in a DNA crime lab, this work is more than just scientific discovery—it’s a calling. Initially drawn to law, Duncan shifted to forensics during college, combining her passion for biology with a desire to serve justice. After rigorous training in both lab work and courtroom testimony, she now helps process thousands of cases each year. “I wanted a job where every day was something different,” Duncan said. “That naturally led me into forensics.”

As the field continues to advance, the integration of DNA, microbes, and insects is transforming the way investigators approach crime scenes—providing crucial answers and ensuring that justice is grounded in science.

Source:https://www.the-scientist.com/making-the-most-of-whole-genome-sequencing-library-prep-72915

This is non-financial/medical advice and made using AI so could be wrong.