Prospective and Retrospective Diagnosis of Barth Syndrome Aided by Next-Generation Sequencing

To establish a genetic and clinical diagnosis in a newborn with fetal-onset dilated cardiomyopathy using next-generation sequencing technologies.

We have conducted the clinical evaluation of the proband and the molecular characterization of his disease by means of whole-exome sequencing. In addition, the clinical evaluation and subsequent genetic screening of five relatives has been performed. This comprises two males with features of left ventricular noncompaction cardiomyopathy, two females suspected of being carriers, and one pregnant female at risk of being a carrier and thereby transmitting the disease to her child.

We have discovered a novel variant in the TAZ gene by means of whole-exome sequencing. This, together with the performance of further clinical analyses, led to an early diagnosis of Barth syndrome in the proband. The genetic screening of the subject's familial group revealed full cosegregation of the variant with another two affected males and identified several female carriers.

The investigation for Barth syndrome must be considered in male babies and young boys with dilated cardiomyopathy and left ventricular noncompaction. Next-generation sequencing technologies provide an accurate and rapid diagnostic tool in prospectively and retrospectively identifying individuals with this Mendelian syndrome.