Abstract
The presence of chromosomes with diffuse centromeres (holocentric chromosomes) has been reported in several taxa since more than fifty years, but a full understanding of their origin is still lacking. Comparative and functional genomics are nowadays furnishing new data to better understand holocentric chromosome evolution thus opening new perspectives to analyse karyotype rearrangements in species with holocentric chromosomes in particular evidencing unusual common features, such as the uniform GC content and gene distribution along chromosomes.