Postmortem Diagnostic Exome Sequencing Identifies a De Novo TUBB3 Alteration in a Newborn With Prenatally Diagnosed Hydrocephalus and Suspected Walker-Warburg Syndrome

Pediatr Dev Pathol. 2018 May-Jun;21(3):319-323. doi: 10.1177/1093526617698611. Epub 2017 Mar 23.

Abstract

Objective Herein, we report a case of a deceased newborn with prenatally detected hydrocephalus. Postnatal findings included abnormal brain imaging and electroencephalogram, optic nerve abnormalities, and elevated creatine kinase (CK). No underlying genetic etiology had been previously identified for the proband, despite testing with a congenital muscular dystrophy gene panel. Methods Diagnostic exome sequencing (DES) was performed on the proband-parents trio, and candidate alterations were confirmed using automated fluorescence dideoxy sequencing. Results Exome sequencing of the proband, mother and father identified a previously unreported apparently de novo heterozygous tubulin, beta-3 ( TUBB3) c.523G>C (p.V175L) alteration in the proband. Conclusion Overall, DES established a likely molecular genetic diagnosis for a postmortem case after traditional testing methods were uninformative. The DES results allowed for reproductive options, such as preimplantation genetic diagnosis and/or prenatal diagnosis, to be available to the parents in future pregnancies.

Keywords: TUBB3 protein; Walker–Warburg syndrome; abnormal brain; clinical diagnostic sequencing; exome; human; hydrocephalus; postmortem diagnosis.

Publication types

  • Case Reports

MeSH terms

  • Exome Sequencing*
  • Fatal Outcome
  • Female
  • Genetic Markers
  • Heterozygote
  • Humans
  • Hydrocephalus / diagnosis*
  • Hydrocephalus / etiology
  • Infant, Newborn
  • Pregnancy
  • Prenatal Diagnosis*
  • Tubulin / genetics*
  • Walker-Warburg Syndrome / complications
  • Walker-Warburg Syndrome / diagnosis*
  • Walker-Warburg Syndrome / genetics

Substances

  • Genetic Markers
  • TUBB3 protein, human
  • Tubulin