title: Mild combined immunodeficiency in identical twins.
mesh_terms: D004200:Diseases in Twins; D006801:Humans; D007111:Immunity, Cellular; D007074:Immunoglobulin G / Q000032:analysis; D007153:Immunologic Deficiency Syndromes / Q000097:blood / Q000235:genetics*; D007223:Infant; D008297:Male
chemical_list: D007074:Immunoglobulin G