Trisomy 20 mosaicism – a subtle phenotype

  • Inês Medeiros Department of Pediatrics, Hospital de Braga
  • Catarina Faria Department of Pediatrics, Hospital de Braga
  • Fábia Carvalho Department of Pediatrics, Hospital de Braga
  • Miguel Gonçalves Rocha Department of Genetics, Hospital de Braga
  • Helena Silva Department of Pediatrics, Hospital de Braga
Keywords: Mosaicism, phenotype, trisomy 20

Abstract

Introduction: Trisomy 20 mosaicism is one of the most common cytogenetic abnormalities found in prenatal diagnosis. The outcome of these pregnancies is normal in most of the reported cases, but clinical implications of diagnosis and prognosis in a long term basis are not clear.
Case report: The authors present a case of trisomy 20 mosaicism, with no prenatal diagnosis, followed-up for a period of 13 years, aiming to demonstrate the existence of a subtle phenotype, which represents a challenge in diagnosis.
Discussion/Conclusion: No specific phenotype has been associated with the cytogenetic findings but certain features, although subtle, appear to be consistent.

References

Hsu L, Kaffe S, Perlis T. A revisit of trissomy 20 mosaicism in prenatal diagnosis – an overview of 103 cases. Prenat Diagn. 1991; 1: 7-15.

Bui T-H, Iselius L, Lindsten J. European collaborative study on prenatal diagnosis: Mosaicism, pseudomosaicism and single abnormal cells in amniotic fluid cell cultures. Prenatal Diagnosis. 1984; 4 (7): 145-162

Beke A, Tóth-Pál E, Hargitai B, Szigeti Z, Papp C, Papp Z. Trissomy 20 mosaicism and nonmosaic trissomy 20: a report of 2 cases. J Reprod Med. 2006; 51 (3): 209-12.

Willis MJ, Bird LM, Dell'Aquilla M, Jones MC. Expanding the Phenotype of Mosaic Trissomy 20. Am J Med Genet A. 2008; 146A: 330-336.

Robinson WP, McGillivray B, Lewis ME, Arbour L, Barrett I, Kalousek DK. Prenatally detected trissomy 20 mosaicism. Prenatal Diagnosis. 2005; 25(3):239-44.

Chen CP, Chang SD, Chueh HY. Discrepancy in the trissomy mosaicism level between cultured amniocytes and uncultured amniocytes in prenatally detected mosaic trissomy 20. Taiwan J Obstet Gynecol. 2013; 145-146.

Bianca S, Boemi G, Barrano B, Cataliotti A, Ingegnosi C, Indaco L, et al. Mosaic trissomy 20: considerations for genetic counseling. Am J Med Genet. 2008; 146A: 1897-8.

Baty BJ, Olson SB, Magenis RE, Carey JC. Trissomy 20 mosaicism in two unrelated girls with skin hypopigmentation and normal intellectual development. Am J Med Genet. 2001; 99: 210-216.

Hartmann A, Hofmann UB, Hoehn H, Broecker EB, Hamm H. Postnatal Confirmation of Prenatally Diagnosed Trissomy 20 Mosaicism in a Patient with Linear and Whorled Nevoid Hypermelanosis. Ped Dermatology. 2004;21 (6): 636-641.

Taibjee SM, Hall D, Balderson D, Larkins S, Stubbs T, Moss C. Keratinocyte cytogenetics in 10 patients with pigmentary mosaicism: identification of one case of trissomy 20 mosaicism confined to keranocytes. Clin Exp Dermatol. 2009; 34 (7): 823-9.

Published
2018-10-17
How to Cite
Medeiros, I., Faria, C., Carvalho, F., Rocha, M. G., & Silva, H. (2018). Trisomy 20 mosaicism – a subtle phenotype. NASCER E CRESCER - BIRTH AND GROWTH MEDICAL JOURNAL, 27(3), 182-184. https://doi.org/10.25753/BirthGrowthMJ.v27.i3.11686
Section
Case Reports

Most read articles by the same author(s)