The Human Type I Keratin Gene Family: Characterization of New Hair Follicle Specific Members and Evaluation of the Chromosome 17q21.2 Gene Domain

December 2004 in “ Differentiation ”

Michael A. Rogers, Hermelita Winter, Lutz Langbein, Raphael Bleiler, Jürgen Schweizer

type I keratin keratin-associated protein K25irs1 K25irs2 K25irs3 K25irs4 Ka35 Ka36 K23 K24 inner root sheath hair follicles epithelial tissues keratin hair follicle keratin epithelial keratin

Studysummary This study identifies six novel keratin genes from the chromosome 17q21.2 region, suggesting their association with hair follicles, while all 27 keratin genes in the domain have been characterized transcriptionally. Our plain-language summary of this paper — not a Tressless recommendation.

The study characterized the type I keratin gene family on chromosome 17q21.2, identifying 27 type I keratin genes and five pseudogenes within an 970 kb domain, which includes a 350 kb region with 32 keratin-associated protein genes. Six previously uncharacterized keratin genes (K25irs1-K25irs4, Ka35, and Ka36) were isolated and found to be associated with hair follicles, specifically the inner root sheath, while K23 and K24 were linked to epithelial tissues. The research confirmed that all 27 keratin genes in this domain have been characterized at the transcriptional level, suggesting a complete set of functional type I keratins in humans.

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