ORPHA:369920

Pontocerebellar hypoplasia type 9

medium confidenceSubtype of disorder

Also known as: PCH9

Publications

42.4th percentile

Trials

Interventional, condition-specific

Researchers

265

Distinct authors in sample

Gene link

AMPD2

Definitive

Readiness

3/6

Stages with a signal

Clinical definition (Orphanet)

A rare, genetic, non-syndromic pontocerebellar hypoplasia characterized by cerebellum and brainstem atrophy, corpus callosum hypo-/aplasia and post-natal microcephaly. Patients typically present profound global , spastic tetraparesis, , cortical visual impairment and, on neuroimaging, abnormal brain morphology that includes pontocerebellar hypoplasia, ''figure of 8'' midbrain appearance, and, more variably, interhemispheric cysts, ventriculomegaly and cerebral dysmyelination.

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.

Orphanet entry

Cross-references

Joined from Mondo / Orphanet. MeSH labels may enter searches; UMLS / OMIM / NCIT are stored for reference.

Additional Mondo synonyms (2)

AMPD2 non-syndromic pontocerebellar hypoplasia · non-syndromic pontocerebellar hypoplasia caused by mutation in AMPD2

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.”

3/6 stages with a signal

An interventional trial matched this condition name on ClinicalTrials.gov — see trials below.

Gene identifiedPresent
Definitive — AMPD2
LiteraturePresent
31 matched papers (28 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 trialPresent
1 matched on ClinicalTrials.gov

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 (AMPD2).

GenCC classification: Definitive.

AMPD2

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?

31 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.

31 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).

28 in the last 10 years · medium confidence · 42.4th percentile (publications denominator)

Phrase hits: 31 · MeSH hits: 0

Open Europe PMC search

Who's working on it?

265

Distinct author names in 31 sampled papers — named people below.

Who's working on it?

People publishing on this condition (sampled Europe PMC records). Affiliation is the most recent found in that sample.

01
Leventer RJ3 papers · 2019
Bruce Lefroy Centre for Genetic Health Research (A.P.L.M., K.P., E.M.Y., J.C.H.S., M.B.D., P.J.L.), Murdoch Childrens Research Institute, Royal Children's Hospital, Parkville, Australia; Bioinformatics Division (V.L., C.B., R.T., M.B.), The Walter and Eliza Hall Institute of Medical Research, Parkville, Australia; Department of Neurology (M.M.R., E.M.Y., R.J.L.) and Department of Paediatrics (A.P.L.M., M.M.R., E.M.Y., M.B.D., D.J.A., R.J.L., P.J.L.), The University of Melbourne, Royal Children's Hospital, Parkville, Australia; Victorian Clinical Genetics Services (D.J.A., G.M.) and Neuroscience Research (M.M.R., R.J.L.), Murdoch Childrens Research Institute, Parkville, Australia; Department of Neurology (E.H.S.), UCSF Benioff Children's Hospital, San Francisco, CA; Clinical Genetics (M.B.D.), Austin Health, Heidelberg, Australia; and Department of Mathematics and Statistics (M.B.) and Department of Medical Biology (R.T., M.B.), The University of Melbourne, Parkville, Australia.
Papers in Europe PMC
02
Lockhart PJ3 papers · 2019
Bruce Lefroy Centre for Genetic Health Research (A.P.L.M., K.P., E.M.Y., J.C.H.S., M.B.D., P.J.L.), Murdoch Childrens Research Institute, Royal Children's Hospital, Parkville, Australia; Bioinformatics Division (V.L., C.B., R.T., M.B.), The Walter and Eliza Hall Institute of Medical Research, Parkville, Australia; Department of Neurology (M.M.R., E.M.Y., R.J.L.) and Department of Paediatrics (A.P.L.M., M.M.R., E.M.Y., M.B.D., D.J.A., R.J.L., P.J.L.), The University of Melbourne, Royal Children's Hospital, Parkville, Australia; Victorian Clinical Genetics Services (D.J.A., G.M.) and Neuroscience Research (M.M.R., R.J.L.), Murdoch Childrens Research Institute, Parkville, Australia; Department of Neurology (E.H.S.), UCSF Benioff Children's Hospital, San Francisco, CA; Clinical Genetics (M.B.D.), Austin Health, Heidelberg, Australia; and Department of Mathematics and Statistics (M.B.) and Department of Medical Biology (R.T., M.B.), The University of Melbourne, Parkville, Australia.
Papers in Europe PMC
03
Bijlsma EK2 papers · 2025
Department of Clinical Genetics, Leiden University Medical Centre, Leiden, The Netherlands.
Papers in Europe PMC
04
Dave-Wala A2 papers · 2020
The Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children's Hospital, Columbus, Ohio 43205, USA.
Papers in Europe PMC
05
Hoffer MJV2 papers · 2025
Department of Clinical Genetics, Leiden University Medical Centre, Leiden, The Netherlands.
Papers in Europe PMC
06
Marsh AP2 papers · 2017
Bruce Lefroy Centre for Genetic Health Research (A.P.L.M., K.P., E.M.Y., J.C.H.S., M.B.D., P.J.L.), Murdoch Childrens Research Institute, Royal Children's Hospital, Parkville, Australia; Bioinformatics Division (V.L., C.B., R.T., M.B.), The Walter and Eliza Hall Institute of Medical Research, Parkville, Australia; Department of Neurology (M.M.R., E.M.Y., R.J.L.) and Department of Paediatrics (A.P.L.M., M.M.R., E.M.Y., M.B.D., D.J.A., R.J.L., P.J.L.), The University of Melbourne, Royal Children's Hospital, Parkville, Australia; Victorian Clinical Genetics Services (D.J.A., G.M.) and Neuroscience Research (M.M.R., R.J.L.), Murdoch Childrens Research Institute, Parkville, Australia; Department of Neurology (E.H.S.), UCSF Benioff Children's Hospital, San Francisco, CA; Clinical Genetics (M.B.D.), Austin Health, Heidelberg, Australia; and Department of Mathematics and Statistics (M.B.) and Department of Medical Biology (R.T., M.B.), The University of Melbourne, Parkville, Australia.
Papers in Europe PMC
07
Mcgillivray G2 papers · 2017
Bruce Lefroy Centre for Genetic Health Research (A.P.L.M., K.P., E.M.Y., J.C.H.S., M.B.D., P.J.L.), Murdoch Childrens Research Institute, Royal Children's Hospital, Parkville, Australia; Bioinformatics Division (V.L., C.B., R.T., M.B.), The Walter and Eliza Hall Institute of Medical Research, Parkville, Australia; Department of Neurology (M.M.R., E.M.Y., R.J.L.) and Department of Paediatrics (A.P.L.M., M.M.R., E.M.Y., M.B.D., D.J.A., R.J.L., P.J.L.), The University of Melbourne, Royal Children's Hospital, Parkville, Australia; Victorian Clinical Genetics Services (D.J.A., G.M.) and Neuroscience Research (M.M.R., R.J.L.), Murdoch Childrens Research Institute, Parkville, Australia; Department of Neurology (E.H.S.), UCSF Benioff Children's Hospital, San Francisco, CA; Clinical Genetics (M.B.D.), Austin Health, Heidelberg, Australia; and Department of Mathematics and Statistics (M.B.) and Department of Medical Biology (R.T., M.B.), The University of Melbourne, Parkville, Australia.
Papers in Europe PMC
08
Peeters-Scholte CMPCD2 papers · 2025
Department of Neurology, Leiden University Medical Centre, Leiden, The Netherlands.
Papers in Europe PMC
09
Pope K2 papers · 2017
Bruce Lefroy Centre for Genetic Health Research (A.P.L.M., K.P., E.M.Y., J.C.H.S., M.B.D., P.J.L.), Murdoch Childrens Research Institute, Royal Children's Hospital, Parkville, Australia; Bioinformatics Division (V.L., C.B., R.T., M.B.), The Walter and Eliza Hall Institute of Medical Research, Parkville, Australia; Department of Neurology (M.M.R., E.M.Y., R.J.L.) and Department of Paediatrics (A.P.L.M., M.M.R., E.M.Y., M.B.D., D.J.A., R.J.L., P.J.L.), The University of Melbourne, Royal Children's Hospital, Parkville, Australia; Victorian Clinical Genetics Services (D.J.A., G.M.) and Neuroscience Research (M.M.R., R.J.L.), Murdoch Childrens Research Institute, Parkville, Australia; Department of Neurology (E.H.S.), UCSF Benioff Children's Hospital, San Francisco, CA; Clinical Genetics (M.B.D.), Austin Health, Heidelberg, Australia; and Department of Mathematics and Statistics (M.B.) and Department of Medical Biology (R.T., M.B.), The University of Melbourne, Parkville, Australia.
Papers in Europe PMC
10
Santen GWE2 papers · 2025
Department of Clinical Genetics, Leiden University Medical Centre, Leiden, The Netherlands.
Papers in Europe PMC

Clinical research

Is a treatment being tested?

interventional trials for this specific condition

1 interventional trial matched this specific condition name; none in our sample are currently recruiting. 1 trial are registered for pontocerebellar hypoplasia, the broader category — shown separately because they may or may not enrol this specific subtype.

Data as of 27 July 2026

1 interventional trial — more than 73% of diseases in the trials denominator have none at all (5114 of 7003; this disease is at the 76.8th percentile).

medium confidence · 76.8th percentile (trials denominator)

Recruiting interventional trials

From the matched ClinicalTrials.gov set

1 interventional trials matched after quoted-phrase search and title/condition post-filter.

No currently recruiting studies in the matched set. Open the same search on ClinicalTrials.gov.

Broader category: pontocerebellar hypoplasia

Interventional trials for the parent category, exclusive of NCT IDs already counted above. Eligibility for this subtype is not guaranteed.

Worth raising with a clinician. How we count trials.

Observational and natural-history studies

1 observational study matches 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.

Recruiting or not-yet-recruiting

NCT06092346·RECRUITING·A Natural History Study Seeks to Understand the Clinical, Genomic, Pharmacological, Laboratory, and Dietary Determinates of Pyrimidine and Purine Metabolism Disorders
Conditions: AMPD3, OMIM*102772, AMP Deaminase Deficiency · AK1, OMIM *103000, Adenylate Kinase Deficiency · AMPD1, OMIM *102770, Myopathy Due to Myoadenylate Deaminase Deficiency · TPMT, OMIM *187680, Thoipurines, Poor Metabolism of·Matched via recall expansion

Open the complete matched search on ClinicalTrials.gov

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 2026-07-26

This 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.

"Pontocerebellar hypoplasia type 9" OR "AMPD2 non-syndromic pontocerebellar hypoplasia" OR "non-syndromic pontocerebellar hypoplasia caused by mutation in AMPD2"

Run this search on Europe PMC

ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):

"Pontocerebellar hypoplasia type 9" OR "AMPD2 non-syndromic pontocerebellar hypoplasia" OR "non-syndromic pontocerebellar hypoplasia caused by mutation in AMPD2" OR "AMPD2"

Recall-expansion terms: AMPD2

Interventional trials matched via: recall-expansion (mesh = registered under a MeSH descriptor no name phrase would catch; recall-expansion = gene / selected parent terms used only for trials).

Study-type breakdown: 1 interventional · 1 observational · 0 expanded access. Only interventional studies enter the trial headline.

Parent-category trials query:

"pontocerebellar hypoplasia"

Query health: ok — strategies attempted: phrase, recall-expansion; with hits: phrase, recall-expansion

Run this search on ClinicalTrials.gov

Synonyms dropped by stoplist: PCH9

Confidence reasoning

Preferred label is multi-word and distinctive
1 synonym(s) dropped by stoplist (may under-count)
No label/synonym collisions with other diseases in this corpus

Ingested 2026-07-27T14:50:36.485Z