GC-MS as a tool for reliable non-invasive prenatal diagnosis of Smith-Lemli-Opitz syndrome but essential also for other cholesterolopathies verification.

Rare multiple congenital malformations/developmental disorders are challenging in clinical diagnosis. The introduction of next-generation sequencing (NGS) has revolutionized this diagnostic by offering multigene panels or whole-exome sequencing. However, if there is no possibility to perform NGS or if we are facing prenatal ultrasound results, clinical diagnostics is even more difficult.