The Catalog of Human Hair Keratins
TLDR Human hair is made up of different keratins, some strong and some weak, with specific types appearing at various stages of hair growth.
The study "The Catalog of Human Hair Keratins" from 1999 identified and characterized nine human type I hair keratins, categorized into three groups based on structural similarities. Using antibodies and two-dimensional Western blots, the researchers identified two series of type I hair keratins: a strongly expressed series (hHa1, hHa3-I/II, hHa4, hHa5) and a weakly expressed series (hHa2, hHa6, hHa7, hHa8). In situ hybridization and immunohistochemical studies revealed that hHa2 and hHa5 were involved in early hair differentiation, while hHa1, hHa3-I/II, hHa4, hHa6, and hHa8 were expressed during later stages of hair formation. The study highlighted the complexity and specificity of keratin expression in different hair follicle compartments, contributing to a detailed understanding of hair structure and function.
