“…Prior approaches to bacterial identification by DNA sequencing have included fluorescent Sanger sequencing of hundreds of small variable regions of 16S ribosomal amplimer clones (19,20), length heterogeneity (LH) PCR for 16S ribosomal variable regions (21), restriction fragment polymorphisms in 16S (19,21), arrays with bacterium-specific probes, such as PhyloChip (22,23), and early applications of NGS (24,25). These methods have been applied to various clinical situations, such as the microbiome of suboptimally controlled asthma (22), cystic fibrosis (19,21), chronic obstructive pulmonary disease (COPD) (24,26,27), bronchiectasis (28), pleurisy (20), forensic assessment of drowning (25), and intubated patients (23). These studies have revealed unexpectedly large numbers of bacterial genera in patients with clinical illnesses and in healthy individuals (29,30).…”