POSITIONAL CLONING OF NOVEL SKIN-SPECIFIC GENES FROM THE HUMAN EPIDERMAL DIFFERENTIATION COMPLEX

The epidermal differentiation complex, located on human chromosomal ba nd 1q21, contains at least 20 genes expressed during epidermal differe ntiation. we constructed a 1.2-Mb YAC contig spanning the SPRR and S10 0 gene clusters. Restriction mapping and FISH confirmed the colinearit y of the contig with the genomic restriction map (A. Volt ct al., 1993 , Genomics 18:92-99). However, the YAC clones revealed several additio nal restriction sites not previously detected in genomic DNA, presumab ly due to CpG methylation. Making use of cDNA selection, we have ident ified three novel cDNAs, all of which map to the SPRR/IVL region. All three transcripts are expressed at high levels in normal and psoriatic skin, but not in cultured keratinocytes or in a variety of cell lines and human tissues. The molecular cloning of this region provides a va luable tool for identifying additional epidermal differentiation genes and for elucidating the relationship between chromatin structure and gene expression during terminal differentiation. (C) 1997 Academic Pre ss.