# De novo CDKN1C variant in Beckwith–Wiedermann spectrum with atypical complications

## TL;DR

A new CDKN1C gene variant in a child with Beckwith–Wiedemann spectrum reveals atypical features and expands understanding of the condition.

## Contribution

A de novo CDKN1C variant is identified in BWSp with atypical features, emphasizing allelic origin analysis.

## Key findings

- A de novo CDKN1C variant was found on the maternally inherited allele in an infant with BWSp.
- The variant excluded other genetic causes and revealed atypical clinical features.
- The study highlights the importance of allelic origin analysis in atypical BWSp cases.

## Abstract

Beckwith–Wiedemann spectrum (BWSp) is a genomic imprinting disorder characterized by a wide range of clinical features. Here we report an infant with BWSp and atypical features, for whom long-read sequencing confirmed a de novo CDKN1C variant that occurred on the maternally inherited allele and excluded other genetic etiologies. These findings not only expand the BWSp concept but also highlight the potential value of allelic origin analysis in cases with atypical presentations.