SMARCB1 and neoplasm: Loss of the second allele in tumor tissue as a second hit for SMARCB1/INI1 inactivation was suggested by sequencing results (Figure 3A) and further supported by multiplex ligation-dependent probe amplification (MLPA) gene dosage analysis that revealed hemizygous deletion of the entire SMARCB1/INI1 gene and flanking chromosome 22q probes in both tumors (Figure 3D-E).