# A Rare Case of Concurrent SNRPB Mutation and 22q11.2 Microduplication in a Child With Cerebro‐Costo‐Mandibular Syndrome

## TL;DR

This paper reports a rare case of a child with both a SNRPB gene mutation and a 22q11.2 microduplication, associated with cerebro-cost-mandibular syndrome.

## Contribution

The novelty is the first documented case of CCMS combined with a 22q11.2 microduplication.

## Key findings

- The patient exhibited features of cerebro-cost-mandibular syndrome alongside a 22q11.2 microduplication.
- This combination may represent a new or under-recognized genetic interaction in developmental disorders.
- The case highlights the variability and complexity of phenotypes associated with 22q11.2 copy number variations.

## Abstract

We present a unique case of an infant born with both a microduplication of 22q11.2 and SNRPB gene mutations suggestive of cerebro‐costo‐mandibular syndrome (CCMS). Microduplications of 22q11 are known to present with a variety of phenotypes ranging from asymptomatic to significant physical and mental health challenges. CCMS is a rare autosomal dominant condition caused by a mutation in the SNRPB gene and typically presents with posterior rib malformations and branchial arch deformities. There have been less than 100 reported cases of CCMS in the literature, and this may be the first documented case of a patient with both CCMS and a 22q11 microduplication.