A mosaic karyotype of 45,X/46,X,psu idic(Y)(q12) in a ten-year-old boy: integrating high-throughput sequencing with cytogenetic technique for precise diagnosis and genetic counselling

BMC Pediatr. 2023 Mar 4;23(1):104. doi: 10.1186/s12887-023-03872-y.

Abstract

Background: Isodicentric Y chromosome (idic(Y)) is the most commonly reported aberration of the human Y chromosome, which is an important cause of abnormal sexual development. The breakpoints of isodicentric Y chromosome mostly occurred in Yq11.2 and Yp11.3, however, the breakpoints in Yq12 are relatively rare.

Case presentation: We described a 10-year-old boy presenting hypospadias, micropenis and short stature, as well as unilateral cryptorchidism without normal testicular seminiferous tubules structure by biopsy. Whole exome sequencing didn't find any pathogenic/likely pathogenic variants related to phenotypes of this patient. Copy number variation sequencing showed the duplication of whole Y chromosome. Subsequently, karyotyping and FISH analyses demonstrated his genetic diagnosis was mosaic 45,X[8]/46,X,psu idic(Y)(q12)[32], with the breakpoint in Yq12.

Conclusions: Our case proved that it would be beneficial to integrate high-throughput sequencing with cytogenetic technique for precise diagnosis, treatment and genetic counselling.

Keywords: Genetic counselling; High-throughput sequencing; Isodicentric Y chromosome; Mosaicism; Precise diagnosis.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Child
  • Cytogenetic Analysis
  • DNA Copy Number Variations*
  • Genetic Counseling*
  • High-Throughput Nucleotide Sequencing
  • Humans
  • Karyotype
  • Karyotyping
  • Male