{"topic_id":"companion_breed_health_warmblood_horse_omia838_horse","category":"companion-breed-health","context":"---\nlicense: permission_granted\ntopic_id: companion_breed_health_warmblood_horse_omia838_horse\ncategory: companion-breed-health\ntitle: \"Warmblood (Horse) — Hydrocephalus (hereditary; OMIA-verified breed predisposition)\"\nlang: en\nsource: \"OMIA (Online Mendelian Inheritance in Animals, University of Sydney) breed-specific hereditary-disorder record, saved verbatim to source_file; C1 substring-verified. Pulled 2026-08-23 from local OMIA database dump.\"\nsource_file: pdf-raw/breed-health/warmblood_horse_omia838_838.txt\ndate_parsed: 2026-08-23\ntokens_estimated: 424\nverification:\n  method: substring_match\n  claims: 6\n  passed: 6\n  date: 2026-08-23\nrecovered: false\npath: companion-breed-health/companion_breed_health_warmblood_horse_omia838_horse/01_companion_breed_health_warmblood_horse_omia838_horse.md\nsource_document: \"OMIA — Online Mendelian Inheritance in Animals (University of Sydney)\"\ncitation:\n  authority: \"OMIA — Online Mendelian Inheritance in Animals (University of Sydney)\"\n  title: \"Warmblood (Horse) — Hydrocephalus (hereditary; OMIA-verified breed predisposition)\"\n  url: \"https://omia.org/OMIA000487/9796/\"\n  retrieved: \"2026-08-23\"\n  ref: \"OMIA breed-specific hereditary-disorder records (omia.org), derived from local OMIA database dump; dataset: https://doi.org/10.25910/2AMR-PV70\"\n  doc_type: \"academic animal-genetics database (breed-specific disorder entries)\"\n  needs_review: false\n\nverification_derived:\n  method: derived_from_dataset\n  source: \"OMIA database dump (omia.xml, local); fields Gene/Variant/Article/OMIM\"\n  note: \"Structured fields (gene, variant rsID/protein change, PubMed/DOI references, OMIM cross-link) extracted from OMIA dump and presented with first-hand values; not verbatim prose.\"---\n\n# Warmblood (Horse) — Hydrocephalus (hereditary; OMIA-verified breed predisposition)\n\nSource: first-hand OMIA (University of Sydney) breed-specific hereditary-disorder record, saved verbatim to `source_file`; every claim below is a C1 byte-substring of it.\n\n## Claims\n\n- `Breed: Warmblood (Horse)`\n- `Disorder: `\n- `Mode of inheritance: Autosomal recessive`\n- `Clin feat: “Hydrocephalus is defined as ‘an active distension of the ventricular system of the brain resulting from inadequate passage of cerebrospinal fluid (CSF) from its point of production within the cerebral ventricles to its point of absorption into the systemic circulation . . .’ Hydrocephalus can be acquired, e.g. due to infection or trauma, or can be hereditary in nature. To our best knowledge, no clear cases of a proven acquired hydrocephalus in horses have been reported in scientific literature. Different types of hydrocephalus have been identified based on the underlying mechanisms: communicating (increased production or impaired CSF absorption) or non-communicating (obstruction in CSF flow) . . . . Also, hydrocephalus can be internal or external, that is an accumulation of CSF respectively within or outside the ventricles of the brain. In horses, both external and internal hydrocephalus . . . have been diagnosed” (Ducro et. al, 2015). {Text provided by Meredith O’Connell, working under the supervision of Professor Ernie Bailey; 24 April 2019}`\n- `Defect: yes`\n- `Prevalence: “Out of 60 stallions that were genotyped using a commercially available DNA test based on the B3GALNT2 mutation, 8 (13.3 %) were carrier of the allele T. Out of 805 broodmares, 139 (17.3 %) were also carrier.” (Ducro et al., 2015). As the authors reported, this gives a frequency of the likely causal variant of 8.5%. {Adapted by FN from text provided by Meredith O’Connell, working under the supervision of Professor Ernie Bailey; 24 April 2019}`\n## Associated gene(s)\nDerived from OMIA database dump (omia.xml, local); structured field, not verbatim prose. First-hand values below are verbatim substrings of the topic's pdf-raw/omia/<phene_id>.txt source file.\n- Gene: Entrez Gene ID 388948668 (no symbol in OMIA GeneSynonym) — OMIA Phene_Gene\n- OMIA molecular-genetics note: Ducro et al. (2015) reported that \"Next generation DNA sequence analysis of 4 cases and 6 controls of gene exons within the [candidate] region [see Mapping section] revealed a [nonsense] mutation in β-1,3-N-acetylgalactosaminyltransferase 2 (B3GALNT2) as the likely cause of hydrocephalus in Friesian horses. The nonsense mutation XM_001491545 c.1423C&gt;T corresponding to XP_001491595 p.Gln475* was…\n\n## Evidence (references)\nDerived from OMIA database dump (omia.xml, local); structured field, not verbatim prose. First-hand values below are verbatim substrings of the topic's pdf-raw/omia/<phene_id>.txt source file.\n- 1993. Diffuse Cerebral Encephalopathy Associated with Hydrocephalus  and Cholesterinic Granulomas in a Horse. Journal of the American Veterinary Medical Association — PubMed:PMID8407539 — OMIA Phene_Article / Article\n- 1996. Cervical meningomyelocele associated with spina bifida in a hydrocephalic miniature colt. Journal of the American Veterinary Medical Association — OMIA Phene_Article / Article\n- 2002. A case of hydrocephalus in a Polish Primitive Horse. Medycyna Weterynaryjna — OMIA Phene_Article / Article\n- 2011. Diagnosis of internal and external hydrocephalus in a warmblood foal using magnetic resonance imaging. Tierarztl Prax Ausg G Grosstiere Nutztiere — PubMed:PMID22138744 — OMIA Phene_Article / Article\n- 1992. Inheritance of hydrocephalus in horses. Equine Vet J — PubMed:PMID1582393 — OMIA Phene_Article / Article\n- 1980. Congenital hydrocephalus in 2 foals. Mod Vet Pract — PubMed:PMID7421786 — OMIA Phene_Article / Article\n- 1979. A case of equine hydrocephalus. N Z Vet J — PubMed:PMID291822 | DOI:10.1080/00480169.1979.34633 — OMIA Phene_Article / Article\n- 1976. Hydrocephalus in an 18-month-old colt. J Am Vet Med Assoc — PubMed:PMID931772 — OMIA Phene_Article / Article\n- 1950. [Hydrocephalus of the colt]. Rec Med Vet Ec Alfort — PubMed:PMID14781419 — OMIA Phene_Article / Article\n- 2013. Phenotypic characteristics of hydrocephalus in stillborn Friesian foals. Vet Pathol — PubMed:PMID23676552 | DOI:10.1177/0300985813488955 — OMIA Phene_Article / Article\n- 2015. A nonsense mutation in B3GALNT2 is concordant with hydrocephalus in Friesian horses. BMC Genomics — PubMed:PMID26452345 | DOI:10.1186/s12864-015-1936-z — OMIA Phene_Article / Article\n- 2017. Genotyping of friesian horses to detect a hydrocephalus-associated c.1423C>T mutation in B3GALNT2 using PCR-RFLP and PCR-PIRA methods: Frequency in stallion horses in México. Mol Cell Probes — PubMed:PMID28011345 | DOI:10.1016/j.mcp.2016.12.005 — OMIA Phene_Article / Article\n- (5 additional references in OMIA)\n\n## Comparative medicine (human OMIM)\nDerived from OMIA database dump (omia.xml, local); structured field, not verbatim prose. First-hand values below are verbatim substrings of the topic's pdf-raw/omia/<phene_id>.txt source file.\n- OMIM:109400 (type: trait) — OMIA Group_OMIM (via OMIA_ID)\n- OMIM:112240 (type: trait) — OMIA Group_OMIM (via OMIA_ID)\n- OMIM:123155 (type: trait) — OMIA Group_OMIM (via OMIA_ID)\n- OMIM:209970 (type: trait) — OMIA Group_OMIM (via OMIA_ID)\n- OMIM:236600 (type: trait) — OMIA Group_OMIM (via OMIA_ID)\n- OMIM:236635 (type: trait) — OMIA Group_OMIM (via OMIA_ID)\n- OMIM:236640 (type: trait) — OMIA Group_OMIM (via OMIA_ID)\n- OMIM:236660 (type: trait) — OMIA Group_OMIM (via OMIA_ID)\n- OMIM:236670 (type: trait) — OMIA Group_OMIM (via OMIA_ID)\n- OMIM:236690 (type: trait) — OMIA Group_OMIM (via OMIA_ID)\n- OMIM:273730 (type: trait) — OMIA Group_OMIM (via OMIA_ID)\n- OMIM:276950 (type: trait) — OMIA Group_OMIM (via OMIA_ID)\n- OMIM:307000 (type: trait) — OMIA Group_OMIM (via OMIA_ID)\n- OMIM:307010 (type: trait) — OMIA Group_OMIM (via OMIA_ID)\n- OMIM:314390 (type: trait) — OMIA Group_OMIM (via OMIA_ID)\n- OMIM:123155 (type: trait) — OMIA Group_OMIM (via OMIA_ID)\n- OMIM:600257 (type: trait) — OMIA Group_OMIM (via OMIA_ID)\n- OMIM:600559 (type: trait) — OMIA Group_OMIM (via OMIA_ID)\n- OMIM:600991 (type: trait) — OMIA Group_OMIM (via OMIA_ID)\n- OMIM:615181 (type: trait) — OMIA Group_OMIM (via OMIA_ID)\n","sources":["companion-breed-health — Warmblood (Horse) — Hydrocephalus (hereditary; OMIA-verified breed predisposition)"],"source":{"authority":"companion-breed-health","title":"Warmblood (Horse) — Hydrocephalus (hereditary; OMIA-verified breed predisposition)","url":"https://pubmed.ncbi.nlm.nih.gov/8407539/","retrieved":"","ref":"PMID 8407539","doc_type":"official source","source_document":"","verification_file":""},"source_document":"","source_file":"","trust":{"authority_tier":"ungraded","fidelity":"verbatim","license":null,"display_grade":"pending"},"tokens_estimated":1383,"generated_at":null,"tip":"Use /api/v1/topics to discover more topics. /api/v1/nutrient for precise single-point queries. /api/v1/cross_compare for 2-3 standard comparisons."}