Psoriasis, peripheral arthritis, sacroiliitis and juvenile chronic arthritis: a family study in relation to segregation of HLA antigens.

A family consisting of 30 individuals has been examined for the presence of psoriasis, peripheral arthritis and sacroiliitis. These clinical conditions have been studied in relation to the inheritance of the HLA-A,B,C and D genetic markers. Eleven out of 15 with the proband's haplotype A1,C-,B37,DW2, have psoriasis and/or arthritis. Asymptomatic sacroiliitis was a common finding. Arthritis was also found among other family members possessing other haplotypes. One young child has been included because she had juvenile chronic arthritis. However, she did not carry the proband's psoriasis associated haplotype.