ORPHA:98868
Southeast Asian ovalocytosis
Also known as: Hereditary ovalocytosis · Melanesian elliptocytosis · Melanesian ovalocytosis · SAO · Stomatocytic elliptocytosis
Query health: suspect — Only one of 2 strategies returned hits (phrase).
Publications
387
71.7th percentile
Trials
0
Interventional, condition-specific
Researchers
936
Distinct authors in sample
Gene link
SLC4A1
Strong
Readiness
2/6
Stages with a signal
Clinical definition (Orphanet)
Southeast Asian ovalocytosis (SAO) is a rare red cell membrane defect characterized by the presence of oval-shaped erythrocytes and with most patients being asymptomatic or occasionally manifesting with mild symptoms such as pallor, jaundice, anemia and gallstones.
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:0008165
- OMIM:166900
- UMLS:C1862322
Additional Mondo synonyms (3)
ovalocytosis, SA type · sao · stomatocytic elliptocytosis
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
Strong — SLC4A1
- LiteraturePresent
387 matched papers (135 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 (SLC4A1).
GenCC classification: Strong.
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?
387
387 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.
387 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).
135 in the last 10 years · medium confidence · 71.7th percentile (publications denominator)
Phrase hits: 387 · MeSH hits: 0
Who's working on it?
936
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.
- 01Bruce LJ10 papers · 2022
Bristol Institute for Transfusion Sciences, NHS Blood and Transplant, Bristol, United Kingdom.
Papers in Europe PMC - 02Yenchitsomanus PT8 papers · 2023
Division of Molecular Medicine, Department of Research and Development, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand.
Papers in Europe PMC - 03
- 04Reithmeier RA7 papers · 2017
Department of Biochemistry, University of Toronto , 1 King's College Circle, Toronto, Ontario, Canada M5S 1A8.
Papers in Europe PMC - 05Flatt JF5 papers · 2022
Bristol Institute for Transfusion Sciences, NHS Blood and Transplant, Bristol, United Kingdom.
Papers in Europe PMC - 06Jajosky PG5 papers · 2023
Biconcavity Inc., 1106 Spring Mill Dr SW, Lilburn, GA 30047, United States.
Papers in Europe PMC - 07Jajosky RP5 papers · 2023
Biconcavity Inc., 1106 Spring Mill Dr SW, Lilburn, GA 30047, United States. Electronic address: rjajosk@emory.edu.
Papers in Europe PMC - 08Laosombat V5 papers · 2015
Department of Pediatrics, Faculty of Medicine, Prince of Songkla University, Hat yai, Thailand. Ivichai@ratree.psu.ac.th
Papers in Europe PMC - 09Sawasdee N5 papers · 2023
Division of Medical Molecular Biology and BIOTEC-Medical Biotechnology Unit, Department of Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand.
Papers in Europe PMC - 10Weatherall DJ5 papers · 2015Papers 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.
medium 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.
"Southeast Asian ovalocytosis" OR "Hereditary ovalocytosis" OR "Melanesian elliptocytosis" OR "Melanesian ovalocytosis" OR "Stomatocytic elliptocytosis" OR "ovalocytosis, SA type"
ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):
"Southeast Asian ovalocytosis" OR "Hereditary ovalocytosis" OR "Melanesian elliptocytosis" OR "Melanesian ovalocytosis" OR "Stomatocytic elliptocytosis" OR "ovalocytosis, SA type" OR "SLC4A1"
Recall-expansion terms: SLC4A1
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
Synonyms dropped by stoplist: SAO
Confidence reasoning
- Preferred label is multi-word and distinctive
- 1 synonym(s) dropped by stoplist (may under-count)
- "Hereditary ovalocytosis" also appears on ORPHA:288
Ingested 2026-07-27T05:37:48.646Z