RT Journal Article SR Electronic T1 Male-only Systemic Lupus JF The Journal of Rheumatology JO J Rheumatol FD The Journal of Rheumatology SP 1480 OP 1487 DO 10.3899/jrheum.090726 VO 37 IS 7 A1 RACHNA AGGARWAL A1 BAHRAM NAMJOU A1 SHIBO LI A1 ANIL D’SOUZA A1 BETTY P. TSAO A1 BENJAMIN F. BRUNER A1 JUDITH A. JAMES A1 R. HAL SCOFIELD YR 2010 UL http://www.jrheum.org/content/37/7/1480.abstract AB Objective. Systemic lupus erythematosus (SLE) is more common among women than men, a ratio of about 10 to 1. We undertook this study to describe familial male SLE within a large familial SLE cohort. Methods. SLE families (2 or more patients) were identified from the Lupus Multiplex Registry and Repository. Genomic DNA and blood samples were obtained using standard methods. Autoantibodies were determined by multiple methods. Medical records were abstracted for SLE clinical data. Fluorescent in situ hybridization (FISH) was performed with X and Y centromere-specific probes, and a probe specific for the Toll-like receptor 7 gene on the X chromosome. Results. Among 523 SLE families, we found 5 families in which all the SLE patients were male. FISH found no yaa gene equivalent in these families. SLE-unaffected primary female relatives from the 5 families with only-male SLE patients had a statistically increased rate of positive antinuclear antibodies compared to SLE-unaffected female relatives in other families. White men with SLE were 5 times more likely to have an offspring with SLE than White women with SLE, but there was no difference in this likelihood among Black men. Conclusion. Because women in the all-male families had positive antinuclear antibodies, and men are more likely to have children with SLE, these data suggest genetic susceptibility factors that act only in men.