Methods: Forty-six Caucasian CVID patients were recruited from UNC and Duke. Blood leukocytes were genotyped, assaying genomic DNA for rs204989 SNP using manufacturer protocols. A retrospective chart review was conducted to determine whether patients had autoimmune disease.
Results: Of the 46 CVID patients, 29 (63%) did not have the protective GPSM3 allele (SNPM/M), 13 (28%) possessed one allele (SNPM/m), and 4 (9%) possessed both alleles (SNPm/m). 17 of the 46 CVID patients had autoimmunity (37%), and 2 had lymphoproliferation (4%). Four of 17 autoimmune patients (23%) possessed at least one copy of the protective allele (SNPm/m or SNPM/m) compared to 11 of 27 non-autoimmune patients (41%). Both lymphoproliferative patients were heterozygous (SNPM/m).
Conclusions: CVID patients with autoimmunity are less likely to possess the GPSM3 protective allele (SNPm/m or SNPM/m). Interestingly, SNP prevalence in CVID was increased overall compared to healthy Caucasians (9% versus 2% SNPm/m and 28% versus 24% SNPM/m), and both lymphoproliferative patients were SNPM/m heterozygous. This observation suggests that this specific GPSM3 allele may be enriched in CVID compared to the general population and could have functional significance.