INTRODUCTION: In contrast with the well-known and described deletion of the 22q11 chromosome region responsible for DiGeorge syndrome, 22q12 deletions are much rarer. Only a few dozen cases have been reported so far. This region contains genes responsible for cell cycle control, chromatin modification, transmembrane signaling, cell adhesion, and neural development, as well as several cancer predisposition genes. CASE PRESENTATION: We present a patient with cleft palate, sensorineural hearing loss, vestibular dysfunction, epilepsy, mild to moderate intellectual disability, divergent strabism, pes equinovarus, platyspondylia, and bilateral schwannoma. Using Microarray-based Comparative Genomic Hybridization (aCGH), we identified the de novo 3.8 Mb interstitial deletion at 22q12.1→22q12.3. We confirmed deletion of the critical NF2 region by MLPA analysis. DISCUSSION: Large 22q12 deletion in the proband encases the critical NF2 region, responsible for development of bilateral schwannoma. We compared the phenotype of the patient with previously reported cases. Interestingly, our patient developed cleft palate even without deletion of the MN1 gene, deemed responsible in previous studies. We also strongly suspect the DEPDC5 gene deletion to be responsible for seizures, consistent with previously reported cases.

Central European Institute of Technology Masaryk University Brno Czech Republic

Department of Internal Medicine Hematology and Oncology Faculty of Medicine Masaryk University and University Hospital Brno Brno Czech Republic

Department of Medical Genetics and Genomics Faculty of Medicine Masaryk University and University Hospital Brno Brno Czech Republic

Department of Neurosurgery St Anne University Hospital Brno and Faculty of Medicine Masaryk University Brno Czech Republic

Outpatient Ward for Genetics Hospital Jihlava Jihlava Czech Republic

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