title: Two cases of the caudal duplication anomaly including a discordant monozygotic twin.
abstract: We present two unrelated patients with various duplications in the caudal region. One patient presented with a duplication of the distal spine from L4, left double ureter, duplication of the vagina and cervix, and duplication of the distal colon. The second patient was diagnosed with a duplication of the colon, bladder, vagina and uterus. The first patient had an unaffected monozygotic twin sister. Dominguez et al. [1993: Am J Dis Child 147:1048-1052] presented six similar cases, and introduced the name "caudal duplication syndrome." The pathogenesis of the caudal duplication anomaly is unclear. The possibility of a polytopic primary developmental field defect or a disruptive sequence are discussed. On the other hand, somatic or germline mutations in certain developmental genes could be involved, as illustrated by the mouse mutations disorganisation and fused. DNA-analysis of the AXIN1 gene, the human homologue of the gene responsible for fused, performed in our first patient, did not show any apparent pathogenic mutation.
authors.affiliation: Department of Clinical Genetics, University Hospital Groningen, Groningen, The Netherlands. h.y.kroes@dmg.azu.nl
authors.forename: H Y
authors.initials: HY
authors.lastname: Kroes
authors.forename: M
authors.initials: M
authors.lastname: Takahashi
authors.forename: R J
authors.initials: RJ
authors.lastname: Zijlstra
authors.forename: J A L L
authors.initials: JA
authors.lastname: Baert
authors.forename: K A
authors.initials: KA
authors.lastname: Kooi
authors.forename: R M W
authors.initials: RM
authors.lastname: Hofstra
authors.forename: A J
authors.initials: AJ
authors.lastname: van Essen
mesh_terms: D000015:Abnormalities, Multiple / Q000235:genetics / Q000473:pathology*; D060466:Axin Protein; D002584:Cervix Uteri / Q000002:abnormalities; D002648:Child; D003106:Colon / Q000002:abnormalities; D005260:Female; D005836:Genitalia, Female / Q000002:abnormalities; D006801:Humans; D007223:Infant; D008159:Lumbar Vertebrae / Q000002:abnormalities*; D011506:Proteins / Q000235:genetics; D012097:Repressor Proteins; D014430:Twins, Monozygotic; D014513:Ureter / Q000002:abnormalities; D001743:Urinary Bladder / Q000002:abnormalities; D014564:Urogenital Abnormalities; D014599:Uterus / Q000002:abnormalities; D014621:Vagina / Q000002:abnormalities
chemical_list: C555451:AXIN1 protein, human; D060466:Axin Protein; D011506:Proteins; D012097:Repressor Proteins