PGLNext analyzes 14 genes (listed above). All genes 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. For EGLN1, only missense variants in the catalytic domain (codons 188-418) are routinely reported. 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 (excluding EGLN1) using read-depth from NGS data with confirmatory multiplex ligation-dependent probe amplification (MLPA) and/or targeted chromosomal microarray.