Multi-tissue cytogenetic analysis for the diagnosis of mosaic Down syndrome: A case report

Clin Case Rep. 2022 Apr 8;10(4):e05604. doi: 10.1002/ccr3.5604. eCollection 2022 Apr.


Less than one percent of individuals with Down syndrome exhibit mosaicism, a biological phenomenon that describes an individual who has two or more genetically distinct cell lines. The percentage of mosaicism in different tissues can impact the presence of clinical findings and hinder cytogenetic diagnosis. We report a case of mosaicism for trisomy 21 diagnosed after multi-tissue cytogenetic analysis of peripheral blood and buccal mucosa, associated with significant intellectual disability, dysmorphic facial features, congenital heart defects, macropenis, and imperforate anus.

Keywords: Down syndrome; buccal smear; chromosome disorders; cytogenetics; macropenis; mosaicism; trisomy 21.

Publication types

  • Case Reports