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Paper text:
gwas : genome - wide association study ; ld : linkage disequilibrium ; maf : minor allele frequency ; mhc : major histocompatibility complex ; psors1-psors7 : psoriasis susceptibility loci identified in genome - wide linkage studies ; snp : single nucleotide polymorphism .
rbw has been a consultant to or speaker for abbott , janssen cilag , merck serono , schering plough and wyeth , all of which manufacture biological drugs for psoriasis .
cemg has been a paid advisor to and/or has received research grants from abbott , janssen - cilag , leo , merck - serono , novartis , pfizer , ucb pharma and wyeth , all of which manufacture drugs used in the treatment of psoriasis .
the authors are supported in part by the manchester national institute for health research , biomedical research centre .
psoriasis is recognized as a complex disease for which multiple genetic and non - genetic factors influence susceptibility . 
 the major susceptibility locus resides in the mhc class i region and , until relatively recently , evidence for non - mhc loci was inconsistent . like many common diseases , 
 knowledge of the genetic basis of this condition has been advanced dramatically in recent times with the advent of genome - wide association studies using single nucleotide polymorphisms . here , we give an overview of current knowledge of genetic risk factors for psoriasis and consider emerging studies that may further add to our understanding of the genetic basis of the disease .