Send to

Choose Destination
J Invest Dermatol. 1993 Jul;101(1 Suppl):56S-59S.

Human hair keratins.

Author information

Ronald O. Perelman Department of Dermatology, N.Y.U. Medical Center, N.Y. 10016.


Human hair keratins were among the first to be studied but it is only recently that sufficient information has been obtained to gain a basic biologic perspective of these proteins. Hair keratins are members of the intermediate filament family of proteins, yet are sufficiently divergent from epidermal keratins to warrant separate classification: type Ia and IIa ("hard"/hair keratins) and type Ib and IIb (epidermal and other "soft" keratins). As with hair keratins from other species, the human proteins may be distinguished from their epidermal counterparts by a relatively higher cysteine content, 7.6% versus 2.9%, respectively. This feature reflects utilization of disulfide bonding in producing a tougher, more durable structure in the tissues in which the hair keratins are distributed. Although prominent in hair, their distribution is not strictly limited to this tissue. A number of molecular characteristics have been elucidated from human hair keratin gene studies including amino acid sequence data for a type Ia hair keratin. Studies of various pedigrees has revealed a fairly wide latitude of variation in human hair keratin expression that is tolerated without associated obvious hair phenotypic change. Thus, a foundation of knowledge regarding these proteins has emerged and continues to evolve.

[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center