Two cases of the caudal duplication anomaly including a discordant monozygotic twin

Am J Med Genet. 2002 Nov 1;112(4):390-3. doi: 10.1002/ajmg.10594.


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.

Publication types

  • Case Reports

MeSH terms

  • Abnormalities, Multiple / genetics
  • Abnormalities, Multiple / pathology*
  • Axin Protein
  • Cervix Uteri / abnormalities
  • Child
  • Colon / abnormalities
  • Female
  • Genitalia, Female / abnormalities
  • Humans
  • Infant
  • Lumbar Vertebrae / abnormalities*
  • Proteins / genetics
  • Repressor Proteins*
  • Twins, Monozygotic*
  • Ureter / abnormalities
  • Urinary Bladder / abnormalities
  • Urogenital Abnormalities*
  • Uterus / abnormalities
  • Vagina / abnormalities


  • AXIN1 protein, human
  • Axin Protein
  • Proteins
  • Repressor Proteins