Medical Genetics Jesse was participating in a gene therapy trial for ornithine transcarboxylase deficiency (oTCD) He died from multiple organ failures 4 days after starting the treatment His death is believed to have been triggered by a severe immune response to the adenovirus carrierMedical Genetics Jesse was participating in a gene therapy trial for ornithine transcarboxylase deficiency (OTCD). He died from multiple organ failures 4 days after starting the treatment. His death is believed to have been triggered by a severe immune response to the adenovirus carrier