, vol. 523, pp. 147–151, 2013.
PTPN221858C>Tgenepolymorphismhasbeenassociatedwithseveralautoimmunedisordersincludingalopecia areata.Theaimofthecurrentstudywastoinvestigatetheeffectoftheinheritedgeneticpolymorphism1858C>T ofPTPN22geneonthepredispositiontosevereformsofalopeciaareataanditseffectontheresponsetoDPCtreat- ment.Toachieveouraim,PTPN221858C>TgenotypingwasperformedbyPCR-basedrestrictedfragmentlength polymorphism (PCR-RFLP) analysis. The study included 103 Egyptian patients with extensive alopecia areata treatedbyDPC.Hundredhealthyageandsexmatchedblooddonorswereincludedinthecurrentstudyasacon- trol group. Results of genotyping showed that PTPN22 CT and TTmutant genotypesweresignificantlyhigher in AApatientscomparedtocontrolsandconferredincreaseriskofAA(OR = 2.601,95%CI = 1.081–6.255).Statis- tical comparison between AA patients with wild and mutant genotypes revealed that the duration of the illness wassignificantlylongerinthoseharboringthemutantgenotypes.Moreover,theassociationofotherautoimmune diseases as atopy and diabetes mellitus was higher in patients with mutant genotypes. Furthermore, PTPN22 1858C>T genetic polymorphism did not affectthe patients' response to DPC immunotherapy