Fetal Corpus Callosum Anomalies: A Review of Underlying Genetic Disorders and Prenatal Testing Options

Abstract

Anomalies of the corpus callosum (CC) are amongst the most common fetal Central Nervous System (CNS) anomalies detectable on ultrasound. Underlying genetic disease plays an important part in defining prognosis. Associations with aneuploidy and submicroscopic chromosomal deletions or duplications have been well demonstrated using chromosomal microarray analysis. Next-generation sequencing techniques such as exome sequencing, have revolutionized the ability to detect monogenic disease in these fetuses. In the context of important recent publications on exome sequencing in prenatal populations, an updated review of genetic testing options in CC anomalies is presented.

Keywords: corpus callosum; cytogenetics; fetal genetic anomaly; prenatal ultrasound; whole exome sequencing.

Figure 1

Parts of the normal corpus callosum at 28 weeks (1—rostrum; 2—genu; 3—body; 4—splenium).

Figure 2

Prenatal imaging of anomalies of the corpus callosum by ultrasound and MRI A) and C) agenesis CC; B) and D) dysplastic CC.