common variable immunodeficiency (cvid) is an antibody deficiency syndrome that often co-occurs in families with selective iga deficiency (igad). this study was designed to investigate the frequency of dr and dq loci of hla class ii region in common variable immunodeficiency (cvid) patients. fifteen iranian patients with cvid or igad (mean age 14.6±5.4, range 4-25 years; 9 male and 6 female) an...