sperm DNA decondensation obsolete fertilization, exchange of chromosomal proteins https://github.com/geneontology/go-ontology/issues/23465 true GO:0035042 sperm-specific histone exchange biological_process OBSOLETE. Replacement of sperm-specific chromosomal proteins with somatic histones, to allow the paternal genome to acquire a nucleosomal chromatin organization compatible with nuclear activity. sperm-specific histone replacement This term has been obsoleted because it represents a molecular function (histone chaperone activity) and a process (sperm DNA decondensation). histone chaperone activity