RESUMEN
The identification of differential gene expression between gray and black hairs is an important study in modern hair pigment research. In this experiment, the authors have applied new methods by the integration of three updated molecular biological tools, T7 RNA polymerase-based RNA amplification, representational difference analysis (RDA), and microarray analysis, to screen the differentially expressed genes in gray and black hairs. The genes more abundantly expressed in black hairs were pigment related proteins, such as Pmel17, 95kD melanocyte-specific secreted glycoprotein, MART-1, tyrosinase, tyrosinase-related protein 1 etc. Also, expression of the selenium-binding protein (hSBP) gene and the spast gene for spastin protein were up-regulated in black hairs compared to those in gray hairs. In gray hairs, many kinds of genes related with keratin, trichohyalin and transmembrane glycoprotein were more expressed. In particular ch 17, hRPK.142_H_19 was expressed in gray hairs as high signal intensity.