Genotype–Phenotype Correlations in a Prospective Cohort Study of Paediatric Plaque Psoriasis: Lack of Correlation Between HLA-C*06 and Family History of Psoriasis
Annet M. Oostveen, Judith G.M. Bergboer, Peter C.M. van de Kerkhof, Patrick L.J.M. Zeeuwen, Elke M.G.J. de Jong, Joost Schalkwijk, Marieke M.B. Seyger
This study aims to investigate associations between observed clinical parameters and known genetic risk factors of psoriasis in a well-defined prospective cohort of paediatric patients with plaque psoriasis (n = 151). Significant associations were found for paediatric-onset psoriasis with ERAP1 (p = 0.002), IL23R (p = 0.01), LCE3C_LCE3B-del (p = 0.00049) and HLA-C*06 (p = 3.15 × 10–30). Psoriasis severity was associated with the single nucleotide polymorphisms tagging IFIH1 and ERAP1 (p < 0.05). An onset before 10 years of age was associated with IL12B (p = 0.02). Nail psoriasis was more often seen in HLA-C*06-negative patients (p = 0.008). Remarkably, family history is clearly not associated with HLA-C*06 in this specific group. The large proportion of patients with a positive family history in HLA-C*06 negative patients (and the lack of correlation between the two) indicates that other genes, either alone or interaction between two or more genes, may have significant effects on heritability.