BrainTumorNext analyzes 29 genes (listed above). All genes (excluding EPCAM) are evaluated by next generation sequencing (NGS) or Sanger sequencing of all coding domains, and well into the flanking 5’ and 3’ ends of all the introns and untranslated regions. The inversion of coding exons 1-7 of the MSH2 gene is detected by NGS and confirmed by MLPA. For ALK, only variants located within the kinase domain (c.3286-c.4149) are routinely reported. For PHOX2B, the polyalanine repeat region is excluded from analysis. Clinically significant intronic findings beyond 5 base pairs are always reported. Intronic variants of unknown or unlikely clinical significance are not reported beyond 5 base pairs from the splice junction. Additional Sanger sequencing is performed for any regions missing or with insufficient read depth coverage for reliable heterozygous variant detection. Potentially homozygous variants, variants in regions complicated by pseudogene interference, and variant calls not satisfying depth of coverage and variant allele frequency quality thresholds are verified by Sanger sequencing.  Gross deletion/duplication analysis is performed for the covered exons and untranslated regions of all sequenced genes using read-depth from NGS data with confirmatory multiplex ligation-dependent probe amplification (MLPA) and/or targeted chromosomal microarray. For EPCAM, only gross deletions encompassing the 3’ end of the gene are reported. For APC, all promoter 1B gross deletions as well as single nucleotide substitutions within the promoter 1B YY1 binding motif (NM_001127511 c.-196_c.-186) are analyzed and reported. Gross deletion/duplication analysis of PMS2 is performed using MLPA. If a deletion is detected in exons 13, 14, or 15 of PMS2, double stranded sequencing of the appropriate exon(s) of the pseudogene, PMS2CL, will be performed to determine if the deletion is located in the PMS2 gene or pseudogene.