Due to genetic heterogeneity of European populations (marked for example by different proportions and frequencies of BRCA1 mutations among German, Polish or Finnish individuals), it cannot be excluded that association power of TRAF3IP2 with psoriasis is modified by many factors and may vary among different populations—as indicated by statistical values described in our Polish series (OR = 2.5, p = 0.0179), German Kiel cohorts (OR = 1.6, p = 5.8e−05, or CASP GWAS dataset (OR = 1.4, p = 3.3 × 10−4) [27]. Here, BRCA1 is linked to psoriasis.