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

This study presents a new method for preparing human hair shaft samples for proteomic analysis, focusing on cuticular keratins. By using a commercial Precellys homogenizer and implementing an overnight tryptic digestion for partial proteolysis, the researchers achieved over 75% protein extraction efficiency. This approach improved keratin sequence coverage and demonstrated high reproducibility, with R² values exceeding 0.95 in quantitative comparisons. The method's robustness and efficiency make it valuable for identifying genetically variant peptides in keratins, which is important for biomedical and forensic applications.