Cytogenetic analysis of 477 psoriatics revealed an increased frequency of aberrations involving chromosome region 11q

Abstract

Psoriasis is an inflammatory skin disorder affecting approximately 3% of the population. Genetic studies published so far have shown a complex genetic inheritance with heterogeneity and a putative major susceptibility locus in the HLA region on chromosome 6. We have collected a large amount of material consisting mostly of small nuclear families in order to perform a genome-wide scan for psoriasis-associated genes. In order to focus the scan properly on possible candidate regions, we performed a cytogenetic analysis of 477 unrelated psoriatics. We divided our findings into sporadic, affecting a minor fraction of the cells, and constitutional, ie they were present in all cells examined. We found three cases of balanced translocation, all of which involved chromosome 11q. Two of these had a breakpoint in q12-13, whilst one involved the telomeric part of chromosome 11q. In order to characterise further the breakpoint on 11q12-13, we used bacterial artificial chromosomes (BACs) analysed by fluorescent in situ hybridisation (FISH). We were able to show that the persons had a close, but not identical breakpoints; they were separated by at least 5 cM. The major atopy locus is located in this region, as well as a locus for insulin-dependent diabetes mellitus, both being conditions with a pathogenetic mechanism involving antigen presentation.

A genome-wide search for genes predisposing to familial psoriasis by using a stratification approach

“…The two findings on chromosome 3, on markers D3S1768 and D3S1551 respectively, were detected when the analysis was made on the stratified material. In a recent study of ours, 477 individuals from different families and affected with psoriasis were cytogenetically analyzed for the presence of chromosomal aberrations (Enerbäck et al 1998). The chromosomal region around D3S1551 has been further analyzed in an extended family set by linkage and association studies.…”

Lymphocyte telomere dynamics and telomerase activity in inflammatory bowel disease: effect of drugs and smoking

“…Accelerated telomere shortening could be one such factor, and this possibility has not so far been explored in IBD PBLs. Telomere shortening is accelerated in PBLs in inflammatory diseases such as rheumatoid arthritis, 23, 24 lupus erythematosus, 25 psoriasis 26, 27 and atopic dermatitis, 26 some of which are also associated with chromosome instability 28–31 …”

Recalcitrant psoriasis vulgaris associated with Laurence–Moon–Biedl syndrome

“…A study that included cytogenetic analysis of 477 psoriatic patients revealed an increased frequency of aberrations involving chromosome region 11q. Some of these were balanced translocations that had a breakpoint in the same q12–13 locus 6 …”