Advantages of Incomplete Digestion in Human Hair Shaft Proteomics: A Focus on Cuticular Keratins

The study investigates the benefits of incomplete digestion in human hair shaft proteomics, particularly focusing on cuticular keratins. It presents a new method that includes a Precellys homogenization step, achieving over 75% efficiency in protein extraction. By using a shorter overnight tryptic digestion, the researchers found that incomplete digestion improved keratin sequence coverage, which is beneficial for forensic identification through genetically variant peptides (GVPs) when DNA is not viable. The method offers enhanced efficiency and reduced analysis time, providing a reliable alternative to traditional DNA analysis for forensic and health-related applications. Despite detecting fewer proteins than other methods, the study achieved high reproducibility and robust results, highlighting the potential of incomplete digestion in proteomic analyses.