HLA DR alloantigens indifferent subsets ofpatients withSj6gren's syndrome andinfamily members

SUMMARY Patients withSjogren's syndrome alone(Ss), Sjogren's syndrome withrheumatoid arthritis (Ss-RA), andSjbgren's syndrome withRaynaud's phenomenon (Ss-RP) weretyped for theHLA DR andMT antigens. Ss-RApatients hadhigher frequencies ofHLA DR4 thandidSs patients. HLA DR4 was also increased infrequency inpatients withSs-RP. Thisgroupofpatients also showedincreases infrequencies ofHLA DR3.MT2frequencies were elevated inall3patient groups,while MT1wasonlyincreased inSs.Threefamilies withmultiple individuals withSjogren's syndrome weretyped forHLA antigens. Theaffected individuals inherited unique combinations of haplotypes, suggesting thepossibility ofhaplotype interaction inpredisposition todisease. Sjogren's syndromeisan autoimmune disease characterised bylymphoplasmocytic infiltration of exocrine glands andnumerousorganandnonorgan-specific autoantibodies.' Thesyndrome occurs alone(primary) orinassociation withother autoimmunerheumatic diseases (secondary), mostcommonlyrheumatoid arthritis.2 Studies onHLA antigen associations inpatients withSjogren's syndrome haveshownclear genetic similarities aswell asdifferencesinthese2 groupsofpatients.' 3 Clinical differences havealso beendescribed inpatients with primary andsecondary Sjogren's syndrome. More specifically, patients withprimary Sjogren's syndromemore oftenhaveextraglandular manifestations thanpatients withsecondary Sjogren's syndrome.4 Raynaud's phenomenon, anintermittentvasospasm ofthedigital arteries, occurs in approximately one-quarter ofthepatients withthe primary disorder.5 Thisstudy showsthat patients withprimary Sjogren's syndrome andRaynaud's phenomenon have different HLA antigen associations compared with patients withprimary Sj6gren's syndrome without Raynaud's phenomenon andwithpatients withSjogren's syndrome andrheumatoid arthritis. Inaddition froma studyof3 families withmorethanone memberaffected bySjogren's syndrome we have