‘Bubble Boy’ Gene Therapy Halted

A second European toddler apparently suffered a leukemia-like side effect from gene therapy that cured him of the rare but deadly “bubble boy disease,” prompting the government on Tuesday to suspend 27 more gene therapy studies while they investigate the risk.

Bubble boy disease — an immune disorder formally called severe combined immunodeficiency, or SCID — is the only disease ever to be cured with gene therapy.

But three months ago, a boy whose life was saved by a SCID gene therapy experiment in France when he was a baby came down with a leukemia-like syndrome at age 3. Wired

Since we are increasingly discovering that various malignancies are tied to activation of dormant genes, this is a theoretical risk of gene therapy. The theory is that the insertion of the gene that corrects the immunodeficiency in this disease turns on a nearby gene that stimulates leukemic transformation. Is this bad luck in the location of the specific locus of therapy for this disease, or an inherent, unforseen generic problem of gene therapy?

By the way, it appears that the two children with gene-therapy-induced leukemias are responding to chemotherapy…