--- license: permission_granted topic_id: companion_breed_health_domestic_shorthair_omia2941_cat category: companion-breed-health title: "Domestic Shorthair — Porphyria, congenital erythropoietic (hereditary; OMIA-verified breed predisposition)" lang: en source: "OMIA (Online Mendelian Inheritance in Animals, University of Sydney) breed-specific hereditary-disorder record, saved verbatim to source_file; C1 substring-verified. Pulled 2026-08-02 from local OMIA database dump." source_file: pdf-raw/breed-health/domestic_shorthair_omia2941_2941.txt date_parsed: 2026-08-02 tokens_estimated: 805 verification: method: substring_match claims: 10 passed: 10 date: 2026-08-02 recovered: false path: companion-breed-health/companion_breed_health_domestic_shorthair_omia2941_cat/01_companion_breed_health_domestic_shorthair_omia2941_cat.md source_document: "OMIA — Online Mendelian Inheritance in Animals (University of Sydney)" citation: authority: "OMIA — Online Mendelian Inheritance in Animals (University of Sydney)" title: "Domestic Shorthair — Porphyria, congenital erythropoietic (hereditary; OMIA-verified breed predisposition)" url: "https://omia.org/OMIA001175/9685/" retrieved: "2026-08-02" ref: "OMIA breed-specific hereditary-disorder records (omia.org), derived from local OMIA database dump; dataset: https://doi.org/10.25910/2AMR-PV70" doc_type: "academic animal-genetics database (breed-specific disorder entries)" needs_review: false
Domestic Shorthair — Porphyria, congenital erythropoietic (hereditary; OMIA-verified breed predisposition)
Source: 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.
Claims
Breed: Domestic Shorthair (Cat)Disorder:Mode of inheritance: Autosomal recessiveSummary: Congenital erythropoietic porphyria (CEP) is a disorder of heme synthesis characterized by erythrodontia (brownish teeth) that fluoresce pink under UV light and reddish-brown urine. No other clinical signs were noted (Clavero et al 2010). The presenting signs are the same as those of acute intermittent porphyria (AIP) in cats. Cats with CEP are deficient in uroporphyrinogen III synthase (UROS) activity, a necessary enzyme in the heme synthesis pathway. This is a potential model for human CEP (OMIM#606938 and #263700), as the mutations occur in the same gene. Edited by Dr. Mark HaskinsClin feat: No clinical signs except for erythrodontia (brownish discolored teeth) and reddish-brown urine. The teeth fluoresce pink under UV light. The dark red pigmented urine is not hematuria or hemoglobinuria. Complete blood counts were normal except for mild normoblastosis, basophilic stippling, and polychromasia (Clavero et al., 2010). Affected cats have normal hydroxymethylbilane (HMB) synthase activity, and greatly decreased uroporphyrinogen III synthase (UROS) activity. Urinary aminolevulinic acid (ALA) and porphobilinogen (PBG) levels are normal, while uroporphyrinogen I levels in urine and plasma are markedly increased (Clavero et al., 2010).Defect: yesPathology: In the normal heme biosynthesis pathway, UROS converts HMB to uroporphyrinogen (URO’gen) III. The causative mutations render UROS unstable, so affected cats are deficient in this enzyme. If UROS is deficient, HMB is nonenzymatically converted to a URO’gen I isomer, which then is enzymatically converted to coproporphyrinogen (COPRO’gen) I. URO’gen I and COPRO’gen I isomers accumulate, and are then oxidized to their corresponding porphyrins – uroporphyrin I (URO I) and coproporphyrin I (COPRO I). URO I and COPRO I isomers then accumulate in erythroid precursors and erythrocytes. When these cells rupture, the isomers are released into circulation and are deposited in teeth, skin, and bones, and are excreted in urine and feces. Deposition in teeth and bones causes the clinically significant discoloration. Excretion in the urine is observed as dark red pigment (Clavero et al., 2010).Prevalence: Cats presenting with brown discolored teeth may have either CEP or AIP (a href=../../../../../../OMIA001493/9685/OMIA:001493-9685/a). There has so far been one genetically confirmed feline case of CEP, resulting from two concurrent mutations in the UROS gene. Neither mutation was present in 100 normal cat alleles (Clavero et al., 2010, Clavero et al., 2009).Control: Since the mode of inheritance for CEP is autosomal recessive, and the mode of inheritance for AIP is autosomal dominant (OMIA ID:2942) testing all cats that present with CEP-like signs is recommended. Breeding of cats with either condition is discouraged.Gen test: Testing for these two mutations in cats that present with a CEP-like phenotype will be helpful in distinguishing CEP cats from those that have AIP (OMIA ID:2942), which is caused by mutations in a different gene (HMB-synthase).
Associated gene(s)
Derived 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.
- Gene: Entrez Gene ID 4476682 (no symbol in OMIA GeneSynonym) — OMIA Phene_Gene
- OMIA molecular-genetics note: By sequencing the candidate gene for this disorder (uroporphyrinogen III synthase; UROS), Clavero et al. (2010) identified two mutations (omia.variant:137) for which a single affected cat was homozygous: "c.140C>T (p.S47F) in exon 3 and c.331G>A (p.G111S) in exon 6". The synergistic interaction of the two mutations caused feline CEP in the reported case (Clavero et al., 2010), a single cat h…
Evidence (references)
Derived 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.
- 1975. Feline congenital erythropoietic porphyria associated with severe anemia and renal disease: clinical, morphologic, and biochemical studies. American Journal of Pathology — PubMed:PMID1231563 — OMIA Phene_Article / Article
- 2010. Feline congenital erythropoietic porphyria: Two homozygous UROS missense mutations cause the enzyme deficiency and porphyrin accumulation. Mol Med — PubMed:PMID20485863 | DOI:10.2119/molmed.2010.00038 — OMIA Phene_Article / Article
- 1979. Increased sensitivity to lead -- animal model: feline porphyria. Med Hypotheses — PubMed:PMID491993 — OMIA Phene_Article / Article
- 1968. Congenital porphyria in the domestic cat (Felis catus): preliminary investigations on inheritance pattern. Am J Vet Res — PubMed:PMID5690689 — OMIA Phene_Article / Article
- 1964. Congenital porphyria in a cat. J Am Vet Med Assoc — PubMed:PMID14215379 — OMIA Phene_Article / Article
- 1970. Feline porphyria: Comparative aspects with porphyria of other animals and man. Animal Models in Biomedical Research III. National Academy of Sciences, Washington DC — OMIA Phene_Article / Article
- 2011. Propagation of multiple cat hereditary disease models following assisted reproduction with frozen semen and embryos. Reproduction, Fertility and Development — OMIA Phene_Article / Article
- 2021. A domestic cat whole exome sequencing resource for trait discovery. Sci Rep — PubMed:PMID33785770 | DOI:10.1038/s41598-021-86200-7 — OMIA Phene_Article / Article
- 2022. Genetic epidemiology of blood type, disease and trait variants, and genome-wide genetic diversity in over 11,000 domestic cats. PLoS Genet — PubMed:PMID35709088 | DOI:10.1371/journal.pgen.1009804 — OMIA Phene_Article / Article
- 2024. Development and validation of animal variant classification guidelines to objectively evaluate genetic variant pathogenicity in domestic animals. Front Vet Sci — PubMed:PMID39703406 | DOI:10.3389/fvets.2024.1497817 — OMIA Phene_Article / Article
Comparative medicine (human OMIM)
Derived 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.
- OMIM:263700 (type: trait) — OMIA Group_OMIM (via OMIA_ID)
verification_derived: method: derived_from_dataset source: "OMIA database dump (omia.xml, local); fields Gene/Variant/Article/OMIM" 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."