Inheritance of Psoriasis in a Utah Kindred

The Genetics of Psoriasis

“…The pedi¬ grees of two large families in Utah and North Carolina were consistent with autosomal dominant inherit¬ ance with incomplete penetrance. 5,6 In the latter study, penetrance was 60%. Statistical studies have shown that siblings of psoriatics were more frequently affected when one parent was affected than when neither par¬ ent was affected.4,7-9 In the study of Steinberg et al, 2% of siblings were affected when neither parent had psoriasis, and 9% when one parent was affected.8 These investigators emphasized that a single gene hy¬ pothesis could not explain their data.…”

Psoriasis: Case Rate – HL-A Antigen Frequency Correlations

“…A familial occurrence of psoriasis has been suggested in several reviews and surveys of psoriasis [6,[9][10][11][15][16][17][18], These approaches, for example Lomholt' s extensive pedigree documentation of the Faroe Islands [10], have examined the type of inheritance pattern and it is generally agreed that psoriasis is an autosomal dominant disorder with 'variable expression' (penetrance) [19][20][21][22][23][24][25][26] which does not eliminate a polygenic inheritance pat tern. With the development of histocompatibility typing (HL-A), several authors have found that psoriatics possess either HL-A B13 or B17 antigens [27][28][29][30][31][32][33][34].…”