Researchers at the Icahn School of Medicine at Mount Sinai introduced LongTrack, a long‑read sequencing and assembly pipeline that tracks microbial strains after fecal microbiota transplantation (FMT). Using Oxford Nanopore and PacBio data, the team traced nearly 650 donor strains that engrafted in recipients and characterized genetic and epigenetic changes up to five years post‑transplant. LongTrack leverages long‑read de novo assembly to resolve co‑existing, closely related strains that short‑read methods struggle to distinguish, offering precise engraftment calls and adaptation signatures. The work, published in Nature Microbiology, included systematic validation against cultured strain ground truth. Investigators said the approach improves strain‑level monitoring for FMT trials, donor selection, and mechanistic studies of microbiome therapeutics.