Genomic structure, promoter characterisation and mutational analysis of the S100A7 gene: exclusion of a candidate for familial psoriasis susceptibility.
We have recently assigned a locus for familial psoriasis (PS) susceptibility to the region containing the epidermal differentiation complex gene cluster on chromosome 1q21. Gene S10OA7 maps within this cluster and is reported to be markedly over-expressed in the skin lesions of psoriatic patients. In order to analyse S100A7 as a candidate for PS susceptibility, we have determined its genomic structure regarding exon-intron boundaries and the transcription start site. The gene is organised in three exons and two introns, spanning 2.7 kb. The 5' flanking region contains AP1- and Sp1-binding motifs and a TATA box. We have performed functional assays by using the beta-galactosidase gene as a reporter and have confirmed that this region has strong promoter activity. To search for nucleotide variation within S100A7, we have designed a set of primers to amplify each exon and the gene promoter. Polymerase chain reaction products from 15 unrelated PS patients selected from 1q-linked pedigrees and 25 normal controls have been characterised by single-strand conformation polymorphism and direct sequencing techniques. These analyses have revealed the presence of two polymorphisms in the promoter region (-559G/A and -563 A/G), neither of which shows preferential association with the disease. Our results indicate that S100A7 can be excluded as a candidate for PS susceptibility.
Semprini
S
S
Department of Biopathology and Diagnostic Imaging, Tor Vergata University of Rome School of Medicine and CSS Mendel Institute, Italy.
Capon
F
F
Bovolenta
S
S
Bruscia
E
E
Pizzuti
A
A
Fabrizi
G
G
Schietroma
C
C
Zambruno
G
G
Dallapiccola
B
B
Novelli
G
G
D001483:Base Sequence; D002135:Calcium-Binding Proteins / Q000235:genetics*; D003001:Cloning, Molecular; D004198:Disease Susceptibility; D030342:Genetic Diseases, Inborn / Q000235:genetics; D006801:Humans; D008969:Molecular Sequence Data; D009154:Mutation; D011401:Promoter Regions, Genetic; D011565:Psoriasis / Q000235:genetics*; D000075023:S100 Calcium Binding Protein A7; D009418:S100 Proteins; D020079:Terminal Repeat Sequences
D002135:Calcium-Binding Proteins; D000075023:S100 Calcium Binding Protein A7; D009418:S100 Proteins; C089242:S100A7 protein, human