Missense Variant Met119Val in ACTB in a Patient with Baraitser-Winter Syndrome Type 1 and Mild Intellectual...

Area of Science:

• Genetics
• Medical Genetics
• Rare Diseases

Background:

• Baraitser-Winter syndrome (BRWS) is a rare disorder characterized by congenital anomalies and developmental delay.
• It is etiologically heterogeneous, often caused by gain-of-function variants in ACTB or ACTG1 genes.

Purpose of the Study:

• To report a novel case of BRWS type 1 in a Brazilian female patient.
• To describe the clinical features and genetic findings, including a potential new phenotypic characteristic.

Main Methods:

• Clinical examination and assessment of dysmorphic features.
• Sanger sequencing of the ACTB gene to identify genetic variants.

Main Results:

• The patient presented with BRWS features, including dysmorphic craniofacial features, oligodontia, partial agenesis of the corpus callosum, and mild developmental delay.
• A heterozygous missense variant (NM_001101.5 (ACTB):c.355A>G (p.Met119Val)) in the ACTB gene was identified.

Conclusions:

• The clinical findings support the diagnosis of BRWS type 1.
• Oligodontia is presented as a potential new feature of the BRWS type 1 phenotype.
• Further functional studies of the identified ACTB variant could elucidate the pathogenesis of BRWS.