title: Annotation of suprachromosomal families reveals uncommon types of alpha satellite organization in pericentromeric regions of hg38 human genome assembly.
abstract: Centromeric alpha satellite (AS) is composed of highly identical higher-order DNA repetitive sequences, which make the standard assembly process impossible. Because of this the AS repeats were severely underrepresented in previous versions of the human genome assembly showing large centromeric gaps. The latest hg38 assembly (GCA_000001405.15) employed a novel method of approximate representation of these sequences using AS reference models to fill the gaps. Therefore, a lot more of assembled AS became available for genomic analysis. We used the PERCON program previously described by us to annotate various suprachromosomal families (SFs) of AS in the hg38 assembly and presented the results of our primary analysis as an easy-to-read track for the UCSC Genome Browser. The monomeric classes, characteristic of the five known SFs, were color-coded, which allowed quick visual assessment of AS composition in whole multi-megabase centromeres down to each individual AS monomer. Such comprehensive annotation of AS in the human genome assembly was performed for the first time. It showed the expected prevalence of the known major types of AS organization characteristic of the five established SFs. Also, some less common types of AS arrays were identified, such as pure R2 domains in SF5, apparent J/R and D/R mixes in SF1 and SF2, and several different SF4 higher-order repeats among reference models and in regular contigs. No new SFs or large unclassed AS domains were discovered. The dataset reveals the architecture of human centromeres and allows classification of AS sequence reads by alignment to the annotated hg38 assembly. The data were deposited here: http://genome.ucsc.edu/cgi-bin/hgTracks?db=hg38&hgt.customText=https://dl.dropboxusercontent.com/u/22994534/AS-tracks/human-GRC-hg38-M1SFs.bed.bz2.
authors.affiliation: Institute of Molecular Genetics, Russian Academy of Sciences, Kurchatov sq. 2, Moscow 123182, Russia ; Department of Genomics and Human Genetics, Vavilov Institute of General Genetics, Russian Academy of Sciences, Moscow 119991, Russia ; Center for Brain Neurobiology and Neurogenetics, Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk 630090, Russia.
authors.forename: V A
authors.initials: VA
authors.lastname: Shepelev
authors.affiliation: Institute of Molecular Genetics, Russian Academy of Sciences, Kurchatov sq. 2, Moscow 123182, Russia ; Center for Brain Neurobiology and Neurogenetics, Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk 630090, Russia.
authors.forename: L I
authors.initials: LI
authors.lastname: Uralsky
authors.affiliation: Institute of Molecular Genetics, Russian Academy of Sciences, Kurchatov sq. 2, Moscow 123182, Russia.
authors.forename: A A
authors.initials: AA
authors.lastname: Alexandrov
authors.affiliation: Research Center of Mental Health, Russian Academy of Medical Sciences, Zagorodnoe sh. 2, Moscow 113152, Russia.
authors.forename: Y B
authors.initials: YB
authors.lastname: Yurov
authors.affiliation: Department of Genomics and Human Genetics, Vavilov Institute of General Genetics, Russian Academy of Sciences, Moscow 119991, Russia ; Center for Brain Neurobiology and Neurogenetics, Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk 630090, Russia ; Department of Psychiatry, Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, MA 01604, USA ; Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow 119234, Russia.
authors.forename: E I
authors.initials: EI
authors.lastname: Rogaev
authors.affiliation: Research Center of Mental Health, Russian Academy of Medical Sciences, Zagorodnoe sh. 2, Moscow 113152, Russia.
authors.forename: I A
authors.initials: IA
authors.lastname: Alexandrov
keywords: Alpha satellite; Centromeres; Higher-order repeats; Suprachromosomal families; hg38 human genome assembly