Int J Biol Sci 2012; 8(2):258-264. doi:10.7150/ijbs.3278 This issue


An Updated Nomenclature for Keratin-Associated Proteins (KAPs)

Hua Gong1, Huitong Zhou1, Grant W. McKenzie1, Zhidong Yu2, Stefan Clerens3, Jolon M. Dyer3, Jeffrey E. Plowman3, Mathew W. Wright4, Reena Arora5, C. Simon Bawden6, Yulin Chen7, Jinquan Li8, Jonathan G. H. Hickford1,✉

1. Gene-Marker Laboratory, Faculty of Agriculture and Life Sciences, PO Box 84, Lincoln University, Lincoln 7647, New Zealand
2. Ruakura Research Centre, AgResearch Limited, Private Bag 3115, Hamilton 3240, New Zealand
3. Lincoln Research Centre, AgResearch Limited, Private Bag 8742, Lincoln 8140, New Zealand
4. HUGO Gene Nomenclature Committee (HGNC), EMBL-EBI, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SD, UK
5. National Bureau of Animal Genetic Resources, PO 129, Karnal 132001, Haryana, India
6. Molecular Biology Laboratory, SARDI Livestock and Farming Systems, Roseworthy Campus, Roseworthy, SA 5371, Australia
7. College of Animal Science and Technology, Northwest A&F University, Yangling 712100, China
8. College of Animal Science, Inner Mongolia Agricultural University, Hohhot 010018, China

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Gong H, Zhou H, McKenzie GW, Yu Z, Clerens S, Dyer JM, Plowman JE, Wright MW, Arora R, Bawden CS, Chen Y, Li J, Hickford JGH. An Updated Nomenclature for Keratin-Associated Proteins (KAPs). Int J Biol Sci 2012; 8(2):258-264. doi:10.7150/ijbs.3278. Available from

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Most protein in hair and wool is of two broad types: keratin intermediate filament-forming proteins (commonly known as keratins) and keratin-associated proteins (KAPs). Keratin nomenclature was reviewed in 2006, but the KAP nomenclature has not been revised since 1993. Recently there has been an increase in the number of KAP genes (KRTAPs) identified in humans and other species, and increasingly reports of variation in these genes. We therefore propose that an updated naming system is needed to accommodate the complexity of the KAPs. It is proposed that the system is founded in the previous nomenclature, but with the abbreviation sp-KAPm-nL*x for KAP proteins and sp-KRTAPm-n(p/L)*x for KAP genes. In this system “sp” is a unique letter-based code for different species as described by the protein knowledge-based UniProt. “m” is a number identifying the gene or protein family, “n” is a constituent member of that family, “p” signifies a pseudogene if present, “L” if present signifies “like” and refers to a temporary “place-holder” until the family is confirmed and “x” signifies a genetic variant or allele. We support the use of non-italicised text for the proteins and italicised text for the genes.

This nomenclature is not that different to the existing system, but it includes species information and also describes genetic variation if identified, and hence is more informative. For example, GenBank sequence JN091630 would historically have been named KRTAP7-1 for the gene and KAP7-1 for the protein, but with the proposed nomenclature would be SHEEP-KRTAP7-1*A and SHEEP-KAP7-1*A for the gene and protein respectively. This nomenclature will facilitate more efficient storage and retrieval of data and define a common language for the KAP proteins and genes from all mammalian species.

Keywords: Keratin-associated protein (KAP) gene (KRTAP), nomenclature, genetic variation, diversity, species.