Helminth Immunology Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, United States; Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
Shenghan Gao
Department of Biochemistry and Molecular Genetics, RNA Bioscience Initiative, University of Colorado School of Medicine, Aurora, United States; Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China
Epidemiology Research Unit (ERU) Department of Veterinary and Animal Sciences, Northern Faculty, Scotland’s Rural College (SRUC), Inverness, United Kingdom
Helminth Immunology Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, United States
Asis Khan
Molecular Parasitology Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, United States
Genomics Unit, Research Technologies Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, United States
Rita G Oliveira
Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
Stella Kepha
London School of Tropical Medicine and Hygiene, London, United Kingdom
Stephen F Porcella
Genomics Unit, Research Technologies Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, United States
Joanne Webster
Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom; Royal Veterinary College, University of London, Department of Pathobiology and Population Sciences, Hertfordshire, United Kingdom
Roy Anderson
Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
Michael E Grigg
Molecular Parasitology Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, United States
Department of Biochemistry and Molecular Genetics, RNA Bioscience Initiative, University of Colorado School of Medicine, Aurora, United States; Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, United States
Helminth Immunology Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, United States
Human ascariasis is a major neglected tropical disease caused by the nematode Ascaris lumbricoides. We report a 296 megabase (Mb) reference-quality genome comprised of 17,902 protein-coding genes derived from a single, representative Ascaris worm. An additional 68 worms were collected from 60 human hosts in Kenyan villages where pig husbandry is rare. Notably, the majority of these worms (63/68) possessed mitochondrial genomes that clustered closer to the pig parasite Ascaris suum than to A. lumbricoides. Comparative phylogenomic analyses identified over 11 million nuclear-encoded SNPs but just two distinct genetic types that had recombined across the genomes analyzed. The nuclear genomes had extensive heterozygosity, and all samples existed as genetic mosaics with either A. suum-like or A. lumbricoides-like inheritance patterns supporting a highly interbred Ascaris species genetic complex. As no barriers appear to exist for anthroponotic transmission of these ‘hybrid’ worms, a one-health approach to control the spread of human ascariasis will be necessary.
