The elimination during embryogenesis of certain chromosomes or chromosomal segments from the cells that form the somatic tissues. Germ cells, however, retain these chromosomes. The process occurs in some ciliates, nematodes, copepods, and insects. The discarded DNA often contains highly repetitive sequences and sometimes genes encoding ribosomal proteins. See Chronology, 1887, Boveri; Ascarididae, C value paradox, genomic equivalence, Parascaris equorum.
Subjects: Genetics and Genomics.