L63: Sorting permutations | 2-break distance problem, lower bound & algorithm

Welcome to Lecture 63 of the course "Algorithmic Thinking in Bioinformatics" by Prof. Manikandan Narayanan. Full Course: https://study.iitm.ac.in/ds/course_pages/BSBT4001.html Video Overview Go beyond simple reversals and explore the full spectrum of genome rearrangements that drive evolution and disease. This lecture focuses on translocations, fusions, and fissions—large-scale chromosomal events frequently observed in cancer genomes and visible through karyotyping.You will learn how to represent these complex events using multi-chromosomal permutations and how to generalize the concept of reversal distance using the two-break distance. By modeling rearrangements as two-break operations on circularized chromosomes, we unify multiple types of rearrangements under one computational framework.The lecture introduces a powerful theorem and algorithm based on breakpoint graphs and cycle decomposition to compute the minimum number of two-break operations needed to transform one genome into another. These methods provide essential insights into genome evolution, cancer biology, and the algorithms that make such discoveries possible. About IIT Madras' online Bachelor of Science programme IIT Madras offers four-year BS programmes that aim to provide quality education to all, irrespective of age, educational background, or location. The BS programme has multiple levels, which provide flexibility to students to exit at any of these levels. Depending on the courses completed and credits earned, the learner can receive a Foundation Certificate from IITM CODE (Centre for Outreach and Digital Education), Diploma(s) from IIT Madras, or BSc/BS Degrees from IIT Madras. For more details, Visit: https://www.iitm.ac.in/academics/study-at-iitm/non-campus-bs-programmes #GenomeRearrangement #Translocation #Fusion #Fission #Reversal #CancerGenomics #TumorEvolution #Karyotyping #MultiChromosomalPermutation #TwoBreakDistance #BreakpointGraph #Cycles #GenomeEvolution #ComputationalBiology #Algorithms #Bioinformatics #Genomics #StructuralVariation #ComparativeGenomics #GenomeArchitecture #GenomeDynamics #MolecularEvolution #GenomeMapping #EvolutionaryGenomics #ChromosomalRearrangements