Novel Postzygotic Variants Associated With Hypomelanosis of Ito Expand the ACTB-Related Neurocutaneous Disease Spectrum.
Estella Castillon, Paul Rollier, Didier Bessis et al.
✦ AI-curated · Sources linked
Case in brief
Three individuals presented with mosaic hypopigmentation along Blaschko's lines, some exhibiting neurodevelopmental features. Deep next-generation sequencing of skin biopsies revealed postzygotic ACTB variants. Individuals #1 and #3 shared a missense variant (p.(Arg335His)), previously noted in a constitutional context, while Individual #2 had a novel in-frame insertion-deletion variant. This case highlights a new phenotype associated with ACTB variants.
What made this case unusual
The identification of a novel in-frame insertion-deletion variant in Individual #2, which has not been previously reported, adds to the understanding of ACTB-related conditions.
Diagnostic / clinical pearl
Clinicians should consider the possibility of postzygotic ACTB variants in patients with mosaic hypopigmentation and associated neurodevelopmental features.
Why it matters
This case expands the phenotypic spectrum of ACTB-related neurocutaneous diseases, highlighting the need for awareness of atypical presentations in genetic conditions.