Inherited immune disorders
IL7R-deficient severe combined immunodeficiency
Also called: IL7R-SCID · IL7RA deficiency · CD127 deficiency · T-B+NK+ SCID · SCID · severe combined immunodeficiency · primary immunodeficiency · T-B+ severe combined immunodeficiency due to IL-7 receptor alpha deficiency
What a donor has to do with this
For some people with this condition, a transplant using blood stem cells from an unrelated donor is part of the treatment guidelines. When a transplant is the right route and no one in the family matches, that donor comes from a registry. Not everyone with this condition has a transplant, and many never need one.
This is our reading of published transplant guidelines for this condition, not a measurement of how many people need a donor. Where a source actually counted donors, the figure and the people it counted are shown further down. Where none did, we say so rather than estimate.
This page is not written out in full yet
We have not written this condition out in full yet. What is on this page — how a donor fits in, who it affects, and the sources behind that — is researched and linked, but the plain-English explanation of the condition itself is still to come.
What the evidence says
- Who it affects
- Typical onset/diagnosis: infants of either sex present in the first months of life with T-B+NK+ SCID. Evidence: U.S. Duke discovery series (1998) and GeneReviews founder-variant synthesis (2023); IL7R c.2T>G is enriched in Weaverland and Groffdale Mennonites and reported with approximately 100% penetrance.
- Treatments other than a transplant
- Antimicrobial prophylaxis and immunoglobulin replacement — supportive/bridge to HCT — multiple regions — No approved disease-specific gene therapy.
- If a transplant is used, the cells come from
- bone marrow: used in opened IEI transplant guidance; disease-specific share was not reported; mobilized peripheral blood stem cells: used in opened IEI transplant guidance; disease-specific share was not reported; umbilical cord blood: used as an alternative in opened IEI transplant guidance; disease-specific share was not reported; dominance: no dominant graft source was reported in the opened disease-specific sources
- How often the donor was unrelated
- Not reported. No source we could read states this for this condition, so we do not give a number. An estimate here would be a guess dressed as evidence.
Where this gets complicated
IL7R-SCID retains B and NK cells, distinguishing it from IL2RG- and JAK3-associated T-B+NK- SCID.; The approximately 100% penetrance figure comes from the 2023 U.S. GeneReviews table for the Weaverland/Groffdale Mennonite founder variant, not worldwide IL7R-SCID.
Registries need people
Joining a registry is a cheek swab and a short health form. You are not matched to a condition — you are matched to a person, and it could be someone with any of the conditions in this library. You are contacted only if you turn out to be a possible match for someone, and you can ask questions and decline before anything else happens.
Related conditions
Others in inherited immune disorders. They are genuinely different diseases with different treatments — the group name is not a diagnosis.
Where this came from
- Combined immunodeficiencies in the genetic differential diagnosis — GeneReviews / NCBI Bookshelf, updated 2026
- Guidelines for hematopoietic stem cell transplantation for inborn errors of immunity — EBMT/ESID Inborn Errors Working Party, 2021
- Defective IL7R expression in T(-)B(+)NK(+) severe combined immunodeficiency — Duke Scholars / Nature Genetics, 1998-12
- Genetic disorders associated with founder variants common in the Mennonite population — GeneReviews / NCBI Bookshelf, 2023