title: High-level organization of isochores into gigantic superstructures in the human genome.
abstract: Human DNA shows a complex structure with compositional features at many scales; the isochores--long DNA segments (~10⁵ bp) of relatively homogeneous guanine-cytosine (G + C) content--are the largest well-documented and well-analyzed compositional structures. However, we report here on the existence of a high-level compositional organization of isochores in the human genome. By using a segmentation algorithm incorporating the long-range correlations existing in human DNA, we find that every chromosome is composed of a few huge segments (~ 10⁷ bp) of relatively homogeneous G + C content, which become the largest compositional organization of the genome. Finally, we show evidence of the biological relevance of these superstructures, pointing to a large-scale functional organization of the human genome.
authors.affiliation: Departamento de Física Aplicada II, Universidad de Málaga, ES-29071, Málaga, Spain. pcarpena@ctima.uma.es
authors.forename: P
authors.initials: P
authors.lastname: Carpena
authors.forename: J L
authors.initials: JL
authors.lastname: Oliver
authors.forename: M
authors.initials: M
authors.lastname: Hackenberg
authors.forename: A V
authors.initials: AV
authors.lastname: Coronado
authors.forename: G
authors.initials: G
authors.lastname: Barturen
authors.forename: P
authors.initials: P
authors.lastname: Bernaola-Galván
mesh_terms: D000465:Algorithms; D001482:Base Composition; D002874:Chromosome Mapping; D002877:Chromosomes, Human / Q000648:ultrastructure; D018899:CpG Islands; D003596:Cytosine / Q000737:chemistry; D004247:DNA / Q000737:chemistry*; D020862:GC Rich Sequence; D015894:Genome, Human; D006147:Guanine / Q000737:chemistry; D006801:Humans; D015233:Models, Statistical; D009690:Nucleic Acid Conformation; D012091:Repetitive Sequences, Nucleic Acid; D017422:Sequence Analysis, DNA
chemical_list: D006147:Guanine; D003596:Cytosine; D004247:DNA