Keratin 6C "chromosome" 12q. Keratin 6A and keratin 6B are encoded by the neighbouring genes, which are identical in intron-exon organization to "KRT6C" and are more than 99% identical in their DNA coding sequences. Mutations in K6C have been identified as being able to cause diffuse and focal palmoplantar keratodermas. This has been identified as a form of Pachyonychia congenita. Keratin 6C Keratin 6C (protein name K6C; gene name "KRT6C"), is a type II cytokeratin, one of a number of isoforms of keratin 6 encoded by separate genes located within the type II keratin gene cluster on human chromosome 12q. This gene
Beta-keratin whose flight capabilities have been questioned, would have had avian, but not feather, β-keratins. The small alvarezsaurid dinosaur "Shuvuuia deserti" shows evidence of a featherlike skin covering. Analysis by Schweitzer "et al." (1999) showed that these featherlike structures consisted of beta-keratin. There are two main forms of keratin, alpha-keratin and beta-keratin. Alpha-keratin is seen in humans and other mammals, beta-keratin is present in birds and reptiles. Beta-keratin is harder than alpha-keratin. Structurally alpha-keratin have alpha-helical coiled coil structure while beta-keratin have twisted beta sheet structure.bIn the case of β-sheets, this allows sterically-unhindered hydrogen bonding between the amino and carboxyl groups