title: Physicians continue to study cause(s) of 'bubble' boy's death.
mesh_terms: D000293:Adolescent; D001402:B-Lymphocytes / Q000473:pathology*; D016026:Bone Marrow Transplantation; D002648:Child; D006801:Humans; D007153:Immunologic Deficiency Syndromes / Q000473:pathology* / Q000628:therapy; D008297:Male