Influences on Female Adolescents' Decisions Regarding Testing for Carrier Status of XSCID
Condition: Severe Combined Immunodeficiency
MeSH terms: Severe Combined Immunodeficiency; Immunologic Deficiency Syndromes
Study type: Observational

Summary: 
      The purpose of this study is to learn what factors influence adolescent girls' decisions
      regarding testing for carrier status of X-Linked Severe Combined Immunodeficiency (XSCID). It
      will provide information about how healthy relatives feel about whether they could be XSCID
      carriers, whether carrier testing should be pursued, and, if so, at what age. Commonly known
      as "Bubble Boy Disease," XSCID is a rare, life-threatening immune system disorder that
      affects only males, but females who carry the gene mutation can pass the disease to their
      male children.

      Adolescent girls 13 to 17 years old who have a relative with XSCID and are known to be at
      risk for being carriers are eligible for this study.

      Participants will receive genetic counseling to help them decide if they want to be tested
      for the XSCID gene. Those who elect to be tested will provide a DNA sample from either a
      blood draw or brushing taken from inside the mouth. They will receive the test results from
      the same genetic counselor they spoke with before the testing.

      All participants will also talk with a psychologist over the phone once a year for 3 years to
      answer questions about how they are feeling and what they know about XSCID. They will be
      asked to discuss their decision and feelings about carrier testing.
    

Detailed description: 
      This protocol studies carrier testing decisions of female adolescents who have a male
      relative with X-linked severe combined immunodeficiency (XSCID). XSCID is a rare
      immunodeficiency that affects only males, although females carrying XSCID mutations can pass
      the disease to their male offspring. In previous generations infant boys with XSCID uniformly
      died, but medical interventions such as bone marrow transplantation and now gene therapy,
      have proven life-saving for many patients. XSCID was mapped in 1987, and the disease gene was
      identified in 1993; these advances made possible patient and carrier diagnosis, which have
      been available on a research basis for 10 years through IRB-approved protocols of Dr. Puck. A
      large sample of XSCID families enrolling in molecular diagnosis protocols participated in her
      psychological study of the impact on adult siblings of having a brother affected with XSCID
      (Protocol OH98-HG-N015, Perception of Carrier Status in Families with X-Linked Severe
      Combined Immunodeficiency, now complete and terminated). That study indicated strong interest
      on the part of at-risk females for carrier diagnosis before reaching the age of adulthood.
      The current protocol is a follow-up protocol that functions in concert with Protocol
      95-HG-0066 (Genetic Analysis of Immune Disorders) to study the decision-making process and
      the impact of carrier testing in female adolescents from families with known XSCID mutations.
      With parental consent, carrier testing for girls from age 13 through age 17 will be discussed
      in a genetic counseling session. The 50% risk of being a carrier and the 50% chance of XSCID
      in male offspring of carriers will be explained. Possible psychological and other benefits
      and harms of testing will be aired. If elected by the girl, XSCID mutation testing will be
      performed by having her enroll in our genetic testing protocol 95-HG-0066. Follow-up
      interviews with all girls enrolled, both tested and not tested, will be conducted at 3 months
      and a year post encounter.
    

Keywords: Genetic; Analysis; Immune; Teenage; Girls; Severe Combined Immune Deficiency (SCID); XSCID; Carrier Testing; X-Linked Disease; Adolescent