ORPHA:34592
Immunodeficiency by defective expression of MHC class I
Also known as: Bare lymphocyte syndrome type 1 · MHC class I deficiency
Query health: suspect — Only one of 2 strategies returned hits (phrase).
Publications
146
63.1th percentile
Trials
0
Interventional, condition-specific
Researchers
1,445
Distinct authors in sample
Gene link
TAP1, TAP2, TAPBP
Definitive
Readiness
2/6
Stages with a signal
Clinical definition (Orphanet)
A rare primary immunodeficiency characterized by severe reduction in the cell surface expression of HLA class I molecules, typically resulting in childhood-onset of chronic bacterial infections of the respiratory tract evolving to widespread bronchiectasis and respiratory insufficiency. Sterile necrotizing granulomatous skin lesions mainly involving the extremities and the mid-face may be observed in some patients. Severe viral infections do not occur as part of the condition. Atypical variants without respiratory or cutaneous manifestations, as well as asymptomatic individuals have been reported.
How rare: <1 / 1 000 000 — fewer than one in a million. In a city the size of Kolkata, that might mean on the order of fifteen people.
Cross-references
Joined from Mondo / Orphanet. MeSH labels may enter searches; UMLS / OMIM / NCIT are stored for reference.
- MONDO:0011476
- UMLS:C1858266
Additional Mondo synonyms (2)
immunodeficiency by defective expression of HLA class 1 · immunodeficiency by defective expression of HLA class type 1
Research stages
Trial readiness signals
Where this condition sits on an open-data research pipeline — not how close a treatment is, and not medical advice. Empty stages often mean “not in these databases under this Mondo ID,” not “impossible.”
2/6 stages with a signal
No matched interventional trial; the gene is known and literature exists — preclinical or natural-history work may still be the practical next step.
- Gene identifiedPresent
Definitive — TAP1, TAP2, TAPBP
- LiteraturePresent
146 matched papers (82 in last 10 years) Source
- Phenotype characterisedNot checked
Not yet enriched from Monarch / HPO
- Animal modelNot checked
Not yet enriched from Monarch / Alliance
- Orphan designationNot checked
FDA/EMA orphan-drug designation not enriched yet
- Interventional trialNot found
No matched interventional trial under our ClinicalTrials.gov rules
Biology
Genes and phenotypes
Gene–disease validity from GenCC, plus phenotypes and animal models joined from Monarch Initiative via Mondo ID — not a clinical diagnosis aid.
Do we know what causes it?
Yes — we know a specific gene responsible (TAP1, TAP2, TAPBP).
GenCC classification: Definitive.
Phenotypes (Monarch / HPO)
Not enriched in this build — Monarch phenotype joins were not run for this record.
Animal models (Monarch / Alliance)
Not enriched in this build.
Literature
Is anyone studying this?
146
146 papers have ever been published on this condition (under this name). For scale, breast cancer has over 700,000. Median papers in the last 10 years for a rare disease in this dataset (publications denominator n=5449) is 41.
146 papers since the earliest indexed year in this search — median last-10-year count for a rare disease in this dataset is 41 (publications denominator n=5449).
82 in the last 10 years · high confidence · 63.1th percentile (publications denominator)
Phrase hits: 146 · MeSH hits: 0
Who's working on it?
1,445
Distinct author names in 146 sampled papers — named people below.
Who's working on it?
No interventional trial matched this name; these authors publish on it in the sampled literature — a practical starting point for contact.
- 01Casanova JL9 papers · 2025
St. Giles Laboratory of Human Genetics of Infectious Diseases, Rockefeller Branch, The Rockefeller University, New York, NY, USA.
Papers in Europe PMC - 02Cunningham-Rundles C8 papers · 2025
Departments of Medicine and Pediatrics, Mount Sinai School of Medicine, New York, NY, USA.
Papers in Europe PMC - 03
- 04Ochs HD7 papers · 2020
Department of Pediatrics, University of Washington and Seattle Children's Research Institute, Seattle, WA, USA.
Papers in Europe PMC - 05Al-Herz W6 papers · 2020
Department of Pediatrics, Faculty of Medicine, Kuwait University, Kuwait City, Kuwait.
Papers in Europe PMC - 06Bousfiha A6 papers · 2020
King Hassan II University, Laboratoire d'Immunologie Clinique, d'Inflammation et d'Allergy LICIA at Faculty of Medicine and Pharmacy, Clinical Immunology Unit, Pediatric Infectiouse Disease Department, Children's Hospital, Ibn Rochd University Hospital, Casablanca, Morocco.
Papers in Europe PMC - 07Klein C6 papers · 2025
Dr von Hauner Children's Hospital, Ludwig-Maximilians-University Munich, Munich, Germany.
Papers in Europe PMC - 08Nonoyama S6 papers · 2015
Department of Pediatrics, National Defense Medical College , Saitama , Japan.
Papers in Europe PMC - 09Picard C6 papers · 2025
Study Center for Primary Immunodeficiencies, Necker Hospital for Sick Children, APHP, Paris, France.
Papers in Europe PMC - 10Chatila T5 papers · 2020
Division of Immunology, Children's Hospital Boston, Boston, MA, USA.
Papers in Europe PMC
Clinical research
Is a treatment being tested?
0
interventional trials for this specific condition
No interventional trial testing a treatment matched this specific condition name on ClinicalTrials.gov (observational studies and pan-disease registries are listed separately when present).
Data as of 27 July 2026
No matched interventional trials. This is true for 73% of diseases in the trials denominator (5114 of 7003). Here are the researchers publishing on it.
high confidence · 36.5th percentile (trials denominator)
Recruiting interventional trials
From the matched ClinicalTrials.gov set
No interventional trial testing a treatment was found for this specific condition name on ClinicalTrials.gov.
See who's working on it — people publishing on this disease are often the practical next contact when no trial is listed.
Where to find support
We do not yet link condition-specific patient organisations. These umbrella groups support undiagnosed and ultra-rare families:
India — NPRD
Last verified 2026-07-26This ORPHAcode is not on our curated NPRD list (direct or Mondo-parent match). That does not decide clinical eligibility; families in India should ask a notified Centre of Excellence about current coverage.
Hand-curated for this project. ORPHAcode mappings are best-effort and may be incomplete or imprecise for umbrella categories. Parent (Mondo) matches mean the policy lists a broader category — confirm eligibility with a Centre of Excellence. Financial entitlements summarised from public policy statements and may change. This is not official government guidance.
How we counted this
Europe PMC query (preferred label + any corrected label + Orphanet and Mondo exact synonyms, stoplisted; unioned with resolved MeSH labels when available). UMLS / OMIM / NCIT cross-references are stored on the overview but are not added to the query string.
"Immunodeficiency by defective expression of MHC class I" OR "Immunodeficiency by defective expression of the MHC class I" OR "Bare lymphocyte syndrome type 1" OR "MHC class I deficiency" OR "immunodeficiency by defective expression of HLA class 1" OR "immunodeficiency by defective expression of the HLA class 1" OR "immunodeficiency by defective expression of HLA class type 1" OR "immunodeficiency by defective expression of the HLA class type 1"
ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):
"Immunodeficiency by defective expression of MHC class I" OR "Immunodeficiency by defective expression of the MHC class I" OR "Bare lymphocyte syndrome type 1" OR "MHC class I deficiency" OR "immunodeficiency by defective expression of HLA class 1" OR "immunodeficiency by defective expression of the HLA class 1" OR "immunodeficiency by defective expression of HLA class type 1" OR "immunodeficiency by defective expression of the HLA class type 1" OR "TAP1" OR "TAP2" OR "TAPBP"
Recall-expansion terms: TAP1, TAP2, TAPBP
Study-type breakdown: 0 interventional · 0 observational · 0 expanded access. Only interventional studies enter the trial headline.
Query health: suspect — strategies attempted: phrase, recall-expansion; with hits: phrase
Run this search on ClinicalTrials.gov
Confidence reasoning
- Preferred label is multi-word and distinctive
- No synonyms dropped by stoplist
- No label/synonym collisions with other diseases in this corpus
Ingested 2026-07-26T23:42:34.321Z