Trisomy 20 mosaicism – a subtle phenotype
Keywords:Mosaicism, phenotype, trisomy 20
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.
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.
How to Cite
Copyright and access
This journal offers immediate free access to its content, following the principle that providing free scientific knowledge to the public provides greater global democratization of knowledge.
The works are licensed under a Creative Commons Attribution Non-commercial 4.0 International license.
Nascer e Crescer – Birth and Growth Medical Journal do not charge any submission or processing fee to the articles submitted.