Reconstructing the complete phased sequences of every chromosome copy in humans are important for medical genetics. The unprecedented advancements in sequencing technologies have opened up new avenues to reconstruct these phased sequences that would enable a deeper understanding of molecular, cellular and developmental processes underlying complex diseases. Despite these interesting sequencing innovations, the highly polymorphic and gene-dense human leukocyte antigen (HLA) are not yet fully phased in the reference genome. The reference genome still contains gaps in multi-megabase repetitive regions, and thus annotating novel expression and methylation results are incomplete and inaccurate, that affect the interpretation of molecular genetics and epigenetics of diseases. There is a pressing need for streamlined, production-level, easy-to-use computational approaches that can reconstruct high-quality chromosome-scale phased sequences, and that can be applied to hundreds of personalized human genomes.
In this talk, first, I will present an efficient combinatorial phasing model that leverages new long-range strand-specific technology and long reads to generate chromosome-scale phasing. Second, I present an efficient algorithm to perform accurate haplotype-resolved assembly of human individuals. This method takes advantage of new long accurate data type (PacBio HiFi) and long-range Hi-C data. We for the first time can generate accurate chromosome-scale phased assemblies with base-level-accuracy of Q50 and continuity of 25Mb within 24 hours per sample, therefore, setting up a milestone in the genomic community. Third, I will present the generalized graph-based method for phased assembly of cancer genomes. This graph framework provides a compact representation to encode various data types and can be applied to genomes of any complexity having varying heterozygous rates and repeat content. Finally, I will present the importance of haplotype-resolved assemblies to various medical applications.