LZTR1‐related spinal schwannomatosis and 7q11.23 duplication syndrome: A complex phenotype with dual diagnosis

Abstract

Dual diagnoses are being increasingly recognized with the advent of next-generation sequencing and array-based technologies. Multilocus molecular diagnoses could result in mere addition of the phenotypes when different organ systems are involved, or could lead to an amalgamated phenotype when there are overlapping clinical features (Posey et al., 2017). Atypical clinical manifestations labeled in the past as apparent novel presentation of the disorder might actually represent an additional genetic disorder. Large studies had revealed multilocus molecular diagnoses in a single patient ranging from 2 to 4.9% (Balci et al., 2017; Posey et al., 2017; Smith et al., 2019). In addition to monogenic disorders, copy number variants (CNVs) and single-nucleotide variants (SNVs) as a part of multiple diagnoses was reported in 11.9% of patients by Posey et al. (2017). Dual diagnosis has also been described to the extent of 0.9% with 22q11.2 syndrome (Cohen et al., 2018). Schwannomatosis is an autosomal dominant disorder characterized by multiple schwannomas along the peripheral