ORPHA:382
Guanidinoacetate methyltransferase deficiency
Also known as: GAMT deficiency
Publications
1,792
Trials
0
Interventional, condition-specific
Researchers
1,316
Distinct authors in sample
Gene link
GAMT
Definitive
Readiness
4/6
Stages with a signal
Clinical definition (Orphanet)
Guanidinoacetate methyltransferase (GAMT) deficiency is a creatine deficiency syndrome characterized by global / (DD/ID), prominent speech delay, autistic/hyperactive behavioral disorders, , and various types of pyramidal and/or extra-pyramidal manifestations.
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:0012999
- MeSH:C537622
- OMIM:612736
- UMLS:C0574080
Additional Mondo synonyms (5)
cerebral creatine deficiency syndrome 2 · cerebral creatine deficiency syndrome type 2 · disorder of guanidinoacetate N-methyltransferase activity · guanidinoacetate N-methyltransferase activity disease · guanidinoacetate methyltransferase deficiency
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.”
4/6 stages with a signal
No matched interventional trial, but a gene association and an animal model are on record — often described as translation-ready / stalled at the clinical step.
- Gene identifiedPresent
Definitive — GAMT
- LiteraturePresent
1,792 matched papers (1,174 in last 10 years) Source
- Phenotype characterisedPresent
52 HPO annotations (e.g. Hypotonia; Seizure; Hyperreflexia) Source
- Animal modelPresent
1 genotype model (Mus musculus) Source
- Orphan designationNot found
No FDA or EMA orphan-drug designation matched this disease via UMLS or preferred name Source
- 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 (GAMT).
GenCC classification: Definitive.
Phenotypes (Monarch / HPO)
52
Associated phenotypes · MONDO:0012999
- Hypotonia
- Seizure
- Hyperreflexia
- Absent speech
- Developmental regression
Showing 5 of 52 — open Monarch for the full list.
Animal models (Monarch / Alliance)
1
Model associations linked to this Mondo ID
- Gamttm1Isb/Gamttm1Isb [background:] involves: 129S1/Sv * 129X1/SvJ·MGI:3044676·Mus musculus
Monarch fetch 2026-07-29
Therapies
Designations, candidates, and chemicals
FDA OOPD and EMA orphan designations, Open Targets clinical candidates, and CTD chemical associations via MyDisease.info. These never change the interventional-trial headline.
Orphan designation (FDA · EMA)
No designation matched this disease via UMLS or preferred name on the FDA OOPD mirror or EMA orphan register. Absence here is not proof that none exists under another wording.
Open Targets candidates
No drugs or clinical candidates returned for this Mondo ID on Open Targets.
CTD chemicals (MyDisease.info)
No CTD chemical associations returned for this Mondo ID.
Literature
Is anyone studying this?
1,792
1,792 papers have been published on this condition. That is a real research literature — still far smaller than common diseases (breast cancer: over 700,000 papers). Median papers in the last 10 years for a rare disease in this dataset (publications denominator n=3967) is 59.
1,792 papers since the earliest indexed year in this search — median last-10-year count for a rare disease in this dataset is 59 (publications denominator n=3967).
1,174 in the last 10 years · low confidence
Phrase hits: 467 · MeSH hits: 0
Who's working on it?
1,316
Distinct author names in 200 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.
- 01Salomons GS17 papers · 2025
Metabolic Laboratory, Department of Clinical Chemistry, Amsterdam Neuroscience, VU Medical Center, Amsterdam, The Netherlands.
Papers in Europe PMC - 02Schulze A16 papers · 2026
Department of Pediatrics, University of Toronto, Toronto, Ontario, Canada.
Papers in Europe PMC - 03Mercimek-Andrews S8 papers · 2025
Department of Medical Genetics Faculty of Medicine and Dentistry University of Alberta Edmonton Alberta Canada.
Papers in Europe PMC - 04Lipshutz GS7 papers · 2025
Department of Surgery, David Geffen School of Medicine at UCLA, 757 Westwood Plaza, Room 8501G, Los Angeles, CA, 90095-7054, USA. glipshutz@mednet.ucla.edu.
Papers in Europe PMC - 05Tkachyova I7 papers · 2026
Research Institute, The Hospital for Sick Children, University of Toronto, Toronto, ON, M5G 1X8, Canada.
Papers in Europe PMC - 06Jakobs C6 papers · 2012Papers in Europe PMC
- 07Longo N6 papers · 2025
Scientific Medical Advisory Board, Association for Creatine Deficiencies, Carlsbad, CA, USA.
Papers in Europe PMC - 08Mercimek-Mahmutoglu S6 papers · 2016
Division of Clinical and Metabolic Genetics, Department of Pediatrics, The Hospital for Sick Children, University of Toronto, Toronto, Canada; Metabolic Laboratory, Department of Clinical Chemistry, VU University Medical Center, Amsterdam, The Netherlands.
Papers in Europe PMC - 09Pasquali M6 papers · 2025
Department of Pathology, University of Utah, Salt Lake City, UT, 84108, USA, PASQUAM@aruplab.com.
Papers in Europe PMC - 10Carducci C5 papers · 2025
Dipartimento di Medicina Sperimentale e Patologia, Università degli Studi di Roma La Sapienza, Rome, Italy. cardu-cla@yahoo.com
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. 2 observational studies did — shown below because natural-history and cohort work can be an important step toward a trial.
Data as of 11 September 2026 · last trial check 11 September 2026
No matched interventional trials. This is true for 77.2% of diseases in the trials denominator (5501 of 7126). Here are the researchers publishing on it.
low confidence · 38.6th 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.
Observational and natural-history studies
2 observational studies match this condition. These do not test a treatment and are not counted in the interventional-trial headline, but they are genuine research: natural-history work often defines the endpoints needed for a future rare-disease trial, and families may be able to enroll.
None of the matched observational studies is currently listed as recruiting.
Other registries (secondary)
Broader net from EU CTIS, ISRCTN, and ICTRP when available — deduped against ClinicalTrials.gov IDs already counted above. Dual-model LLM relevance gates what we keep. These rows are not added to the interventional headline.
raw 0 · after dedupe 0 · already on CT.gov 0 · kept 0 · parent 0 · uncertain 0 · dropped 0 · fetched 2026-07-29
Source notes: ictrp: Error: ICTRP public search unavailable (WHO portal is SPA-only; SOAP needs partnership). Tried: https://apps.who.int/tri
No secondary-registry studies passed dual-model relevance for this condition name (after dedupe).
Where to find support
Condition-specific patient organisations, when Orphanet lists them, are on the disease’s Orphanet page. We also link umbrella groups that support undiagnosed and ultra-rare families.
Orphanet entry for Guanidinoacetate methyltransferase deficiency — check Associations / patient organisations on that page.
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.
("Guanidinoacetate methyltransferase deficiency" OR "GAMT deficiency" OR "cerebral creatine deficiency syndrome 2" OR "cerebral creatine deficiency syndrome type 2" OR "disorder of guanidinoacetate N-methyltransferase activity" OR "disorder of the guanidinoacetate N-methyltransferase activity" OR "guanidinoacetate N-methyltransferase activity disease") OR ("GAMT" OR "GAMT syndrome" OR "GAMT-related")ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):
"Guanidinoacetate methyltransferase deficiency" OR "GAMT deficiency" OR "cerebral creatine deficiency syndrome 2" OR "cerebral creatine deficiency syndrome type 2" OR "disorder of guanidinoacetate N-methyltransferase activity" OR "disorder of the guanidinoacetate N-methyltransferase activity" OR "guanidinoacetate N-methyltransferase activity disease"
Study-type breakdown: 0 interventional · 2 observational · 0 expanded access. Only interventional studies enter the trial headline.
Query health: ok — strategies attempted: phrase; 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
- Publication count (1792) is implausibly high for prevalence class "<1 / 1 000 000" — treat as possible over-matching, not a measure of research intensity
Ingested 2026-07-26T13:38:55.753Z