Search for the psoriasis susceptibility gene: the Newfoundland Study.

The authors review early pioneering research on the genetics of psoriasis and recently published independent and collaborative investigations searching for the psoriasis susceptibility genes. We describe the research design and current plans for a joint pursuit between the Psoriasis Research Institute, the Memorial University of Newfoundland, and Chiroscience R&D, Inc., for susceptibility genes. A unique study sample from Newfoundland, drawn from affected and unaffected members of multiplex families and relatives, provides a nearly homogeneous isolated population. Families reflect English, Scottish, and Irish ancestry, and have been in residence in Newfoundland for over 300 years. The prevalence of psoriasis is estimated to be 2 to 3%. Familial psoriasis occurs in over 85% of families, with at least one affected member. The experimental strategy using linkage analysis and linkage disequilibrium analysis of the collected tissue bank are discussed, emphasizing prospects for the future outcome of the research findings.