Investigation of the association between psoriasis and human leucocyte antigens A by means of meta‐analysis

Abstract

Psoriasis is associated with a number of HLA-A alleles, some are susceptible, some are protective. The association of some alleles is different in terms of different races, clinical types and onset age.

Genetic and Hormonal Determinations in a Pair of Identical Twins with Early Onset Psoriasis Vulgaris: Case Report and a Brief Review of the Literature

“…The association between psoriasis and other alleles, such as HLA-A, was investigated before, but only a moderate association was found (2). Knowing that early onset psoriasis is associated with the presence of HLA-Cw6, we aimed to confirm this hypothesis for our subjects, but the results were negative.…”

“…Two main types of psoriasis have been suggested: type I with onset before or at the age of 40, positive family history and frequent association with Human Leukocyte Antigen Cw6 (HLACw6); and type II with onset after the age of 40, negative family history and a normal frequency of the Cw6 allele (2).…”

Evaluation of Psoriasis Patients

“…Psoriasis can occur at any age, but the average age of onset for psoriasis is 33 years and the two peaks of the disease onset are between 16 and 22 years of age and 57-60, respectively [6,8]. It is important to determine the date/age of onset in order to classify psoriasis according to the date of onset into type I (onset before or at the age of 40, positive family history and frequent association with Human Leukocyte Antigen Cw6, noted HLACw6) or type II (onset after the age of 40, negative family history and normal frequency of the Cw6 allele [9]. Positive family history for psoriasis patients is common in 30% up to 90% of cases, as genetic factors have an important role in the disease susceptibility and expression [10][11][12].…”