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Updated: Dec 23, 2025

Manipulation of Ploidy in Caenorhabditis elegans
Published on: March 15, 2018
Sex chromosome evolution in parasitic nematodes of humans
Jeremy M Foster1, Alexandra Grote2, John Mattick3
1Division of Protein Expression & Modification, New England Biolabs, Ipswich, MA, 01938, USA.
Abstract:
Sex determination mechanisms often differ even between related species yet the evolution of sex chromosomes remains poorly understood in all but a few model organisms. Some nematodes such as Caenorhabditis elegans have an XO sex determination system while others, such as the filarial parasite Brugia malayi, have an XY mechanism. We present a complete B. malayi genome assembly and define Nigon elements shared with C. elegans, which we then map to the genomes of other filarial species and more distantly related nematodes. We find a remarkable plasticity in sex chromosome evolution with several distinct cases of neo-X and neo-Y formation, X-added regions, and conversion of autosomes to sex chromosomes from which we propose a model of chromosome evolution across different nematode clades. The phylum Nematoda offers a new and innovative system for gaining a deeper understanding of sex chromosome evolution.
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