Long-Term Follow-Up of Recipient of Gene Transfer Research

If participant received retroviral gene therapy, blood test performed to check for a type of infection called the replication-competent retrovirus (RCR). Blood (up to 4 tablespoons each time) drawn every 3 months for first year after gene transfer therapy and once a year after that.

"Once a year during Years 1-5, questionnaire completions that asks about medical history (general health, the status of any medical conditions, and any illnesses or hospitalizations that may have occurred). It should take about 15-30 minutes to complete.~Once a year during Years 6-15, completion of mailed questionnaire. Participant will be asked about medical history (including if participant has had any children since the infusion) and whether there have been any changes in contact information. The questionnaires should take about 15-30 minutes each time."