{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,24]],"date-time":"2026-10-24T01:13:21Z","timestamp":1792804401362,"version":"4.5.0"},"reference-count":43,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2023,1,5]],"date-time":"2023-01-05T00:00:00Z","timestamp":1672876800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the Museum National d\u2019Histoire Naturelle","id":[{"id":"https:\/\/ror.org\/03wkt5x30","id-type":"ROR","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Genes"],"abstract":"<jats:p>Amongst the 460 karyotypes of Polyphagan Coleoptera that we studied, 50 (10.8%) were carriers of an X autosome rearrangement. In addition to mitotic metaphase analysis, the correct diagnosis was performed on meiotic cells, principally at the pachytene stage. The percentages of these inter-chromosomal rearrangements, principally fusions, varied in relation to the total diploid number of chromosomes: high (51%) below 19, null at 19, low (2.7%) at 20 (the ancestral and modal number), and slightly increasing from 7.1% to 16.7% from 22 to above 30. The involvement of the X in chromosome fusions appears to be more than seven-fold higher than expected for the average of the autosomes. Examples of karyotypes with X autosome rearrangements are shown, including insertion of the whole X in the autosome (ins(A;X)), which has never been reported before in animals. End-to-end fusions (Robertsonian translocations, terminal rearrangements, and pseudo-dicentrics) are the most frequent types of X autosome rearrangements. As in the 34 species with a 19,X formula, there was no trace of the Y chromosome in the 50 karyotypes with an X autosome rearrangement, which demonstrates the dispensability of this chromosome. In most instances, C-banded heterochromatin was present at the X autosome junction, which suggests that it insulates the gonosome from the autosome portions, whose genes are subjected to different levels of expression. Finally, it is proposed that the very preferential involvement of the X in inter-chromosome rearrangements is explained by: (1) the frequent acrocentric morphology of the X, thus the terminal position of constitutive heterochromatin, which can insulate the attached gonosomal and autosomal components; (2) the dispensability of the Y chromosome, which considerably minimizes the deleterious consequences of the heterozygous status in male meiosis, (3) following the rapid loss of the useless Y chromosome, the correct segregation of the X autosome\u2013autosome trivalent, which ipso facto is ensured by a chiasma in its autosomal portion.<\/jats:p>","DOI":"10.3390\/genes14010150","type":"journal-article","created":{"date-parts":[[2023,1,6]],"date-time":"2023-01-06T01:48:19Z","timestamp":1672969699000},"page":"150","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Why Are X Autosome Rearrangements so Frequent in Beetles? A Study of 50 Cases"],"prefix":"10.3390","volume":"14","author":[{"given":"Bernard","family":"Dutrillaux","sequence":"first","affiliation":[{"name":"Institut de Syst\u00e9matique, \u00c9volution, Biodiversit\u00e9, ISYEB-UMR 7205\u2013CNRS, MNHN, EPHE, Sorbonne Universit\u00e9, 57 rue Cuvier CP50 F, 75005 Paris, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anne-Marie","family":"Dutrillaux","sequence":"additional","affiliation":[{"name":"Institut de Syst\u00e9matique, \u00c9volution, Biodiversit\u00e9, ISYEB-UMR 7205\u2013CNRS, MNHN, EPHE, Sorbonne Universit\u00e9, 57 rue Cuvier CP50 F, 75005 Paris, France"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,5]]},"reference":[{"key":"ref_1","unstructured":"White, M.J.D. (1978). Modes of Speciation, Cambridge University Press."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"251","DOI":"10.1007\/BF00272830","article-title":"Chromosomal evolution in Primates: Tentative phylogeny from Microcebus murinus (Prosimian) to man","volume":"48","author":"Dutrillaux","year":"1979","journal-title":"Hum. Genet."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"372","DOI":"10.1038\/190372a0","article-title":"Gene action in the X-chromosome of the mouse (Mus musculus L.)","volume":"190","author":"Lyon","year":"1961","journal-title":"Nature"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"400","DOI":"10.1038\/nature03479","article-title":"X-inactivation profile reveals extensive variability in X-linked gene expression in females","volume":"434","author":"Carrel","year":"2005","journal-title":"Nature"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"131","DOI":"10.1038\/379131a0","article-title":"Requirement for Xist in X chromosome inactivation","volume":"379","author":"Penny","year":"1996","journal-title":"Nature"},{"key":"ref_6","unstructured":"Sandberg, A.A. (1983). Replication studies and demonstration of position effect in rearrangements involving the Human X chromosome. Cytogenetics of the Mammalian X Chromosome, Part A, Basic Mechanisms of X Chromosome Behavior, Alan R Liss Inc."},{"key":"ref_7","unstructured":"Sandberg, A.A. (1983). X-autosome translocations in the mouse: Their characterization and use as tools to investigate gene inactivation and gene action. Cytogenetics of the Mammalian X Chromosome, Part A, Basic Mechanisms of X Chromosome Behavior, Alan R Liss Inc."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"20","DOI":"10.1086\/301922","article-title":"The spreading of X inactivation into autosomal material of an X;autosome translocation: Evidence for a difference between autosomal and X-chromosomal DNA","volume":"63","author":"White","year":"1998","journal-title":"Am. J. Hum. Genet."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"497","DOI":"10.1016\/S1534-5807(03)00093-5","article-title":"H2AX is required for chromatin remodeling and inactivation of sex chromosomes in male meiosis","volume":"4","author":"Mahadevaia","year":"2003","journal-title":"Dev. Cell"},{"key":"ref_10","first-page":"164","article-title":"Phylog\u00e9nie chromosomique chez les Sciuridae, Gerbillidae et Muridae, et \u00e9tude d\u2019esp\u00e8ces appartenant \u00e0 d\u2019autres familles de Rongeurs","volume":"50","author":"Petit","year":"1986","journal-title":"Mammalia"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"34","DOI":"10.1007\/s00412-004-0292-6","article-title":"Viability of X-autosome translocations in mammals: An epigenetic hypothesis from a rodent case-study","volume":"113","author":"Dobigny","year":"2004","journal-title":"Chromosoma"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"369","DOI":"10.1023\/B:CHRO.0000034098.09885.e6","article-title":"Autosome and sex chromosome diversity among the African pygmy mouse, sub-genus Nannomys (Muridae; Mus)","volume":"12","author":"Veyrhunes","year":"2004","journal-title":"Chromosome Res."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"216","DOI":"10.1093\/oxfordjournals.jhered.a111565","article-title":"Chromosomal evolution in Gazelles","volume":"86","author":"Vassard","year":"1995","journal-title":"J. Hered."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"251","DOI":"10.1007\/BF00284758","article-title":"A dynamic study in two cases of X chromosome translocation","volume":"41","author":"Mattei","year":"1978","journal-title":"Hum. Genet."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"158","DOI":"10.1159\/000131804","article-title":"Complex chromosomal evolution of sex chromosomes in Gerbillidae","volume":"34","author":"Benazzou","year":"1982","journal-title":"Cytogenet. Genome Res."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"161","DOI":"10.1159\/000132315","article-title":"Synaptonemal complexes in Gerbillidae: Probable role of intercalated heterochromatin in autosome-gonosome translocations","volume":"43","author":"Ratomponirina","year":"1986","journal-title":"Cytogenet. Genome Res."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"179","DOI":"10.3897\/CompCytogen.v13i2.34746","article-title":"Different behavior of C-banded peri-centromeric heterochromatin between sex chromosomes and autosomes in Polyphagan beetles","volume":"13","author":"Dutrillaux","year":"2019","journal-title":"Comp. Cytogenet."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"336","DOI":"10.1093\/gbe\/evq024","article-title":"Hyperexpression of the X chromosome in both sexes results in extensive female bias of X-linked genes in the flour beetle","volume":"2","author":"Prince","year":"2010","journal-title":"Genome Biol. Evol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"3","DOI":"10.1186\/jbiol30","article-title":"Global analysis of X chromosome dosage compensation","volume":"5","author":"Gupta","year":"2006","journal-title":"J. Biol."},{"key":"ref_20","unstructured":"Smith, S.G., and Virkki, N. (1978). Animal Cytogenetics, Volume 3: Insecta5: Coleoptera, Gebr\u00fcder Borstraeger."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"97","DOI":"10.1159\/000478075","article-title":"Evolution of the sex chromosomes in beetles. I. The loss of the Y chromosome","volume":"152","author":"Dutrillaux","year":"2017","journal-title":"Cytogenet. Genome Res."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"43","DOI":"10.1159\/000200081","article-title":"Sex chromosome rearrangements in Polyphaga beetles","volume":"3","author":"Dutrillaux","year":"2009","journal-title":"Sex. Dev."},{"key":"ref_23","unstructured":"ISCN 1985 (1985). An International System for Human Cytogenetic Nomenclature, S Karger."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"481","DOI":"10.14411\/eje.2010.056","article-title":"(Ovo-) viviparity in the darkling beetle, Alegoria castelnaui (Tenebrionnae: Ulomini), from Guadeloupe","volume":"107","author":"Dutrillaux","year":"2010","journal-title":"Eur. J. Entomol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"348","DOI":"10.1080\/00379271.2019.1637779","article-title":"The chromosomes of Lepturinae (Coleoptera: Cerambycidae) II. A study of eight more species, with focus on Desmocerus palliatus","volume":"55","author":"Dutrillaux","year":"2019","journal-title":"Ann. Soc. Entomol. Fr."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"443","DOI":"10.1080\/21686351.1970.12277940","article-title":"Etude cytog\u00e9n\u00e9tique de quatre esp\u00e8ces de prioniens Col. Crambycidae)","volume":"6","author":"Dutrillaux","year":"1970","journal-title":"Ann. Soc. Entomol. Fr."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"417","DOI":"10.1007\/s10577-007-1133-2","article-title":"Nucleolus and chromosome relationships at pachynema in four Scarabaeoidea (Coleoptera) species with various combinations of NOR and sex chromosomes","volume":"15","author":"Dutrillaux","year":"2007","journal-title":"Chromosome Res."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"909","DOI":"10.1007\/s10577-006-1098-6","article-title":"Meiotic behavior of a new complex X-Y-autosome translocation and amplified heterochromatin in Jumnos ruckeri (Saunders) (Coleoptera, Scarabaeidae, Cetoniinae)","volume":"14","author":"Macaisne","year":"2006","journal-title":"Chromosome Res."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"537","DOI":"10.5252\/z2013n4a7","article-title":"Chromosome analyses challenge the taxonomic position of Augosoma centaurus Fabricius, 1775 (Coleoptera: Scarabaeidae: Dynastinae) and the separation of Dynastini and Oryctini","volume":"35","author":"Dutrillaux","year":"2013","journal-title":"Zoosystema"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1159\/000351210","article-title":"A South American origin of the genus Dynastes (Coleoptera: Scarabaeidae: Dynastinae) demonstrated by chromosome analyses","volume":"141","author":"Dutrillaux","year":"2013","journal-title":"Cytogenet. Genome Res."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"81","DOI":"10.1080\/00379271.2007.10697497","article-title":"Pr\u00e9sence d\u2019un caryotype tr\u00e8s original \u00e0 53-54 chromosomes chez Vesperus xatarti Mulsant 1839 (Coleoptera: Cerambycidae; Vesperinae)","volume":"43","author":"Dutrillaux","year":"2006","journal-title":"Ann. Soc. Entomol. Fr."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"101","DOI":"10.1007\/BF00127130","article-title":"Karyological differences among Tenebrionidae (Coleoptera)","volume":"80","author":"Juan","year":"1990","journal-title":"Genetica"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"121","DOI":"10.1111\/j.1601-5223.2001.00121.x","article-title":"Cytogenetics of height species of Chauliogathus Henzt, 1830: Implications on the ancestral karyotype in Cantharidae (Coleoptera)","volume":"134","author":"Machado","year":"2001","journal-title":"Hereditas"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"293","DOI":"10.1007\/s10709-006-9106-5","article-title":"A chromosomal investigation of some British Cantharidae","volume":"130","author":"James","year":"2007","journal-title":"Genetica"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"45","DOI":"10.14411\/eje.2018.006","article-title":"Loss of Y chromosome may be a synapomorphy of the tribe Lepturini (Coleoptera: Cerambycidae: Lepturinae)","volume":"115","author":"Dutrillaux","year":"2018","journal-title":"Eur. J. Entomol."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"304","DOI":"10.1159\/000448931","article-title":"Interstitial NORs, fragile sites, and chromosome Evolution: A not so simple relationship\u2014The example of Melolontha melolontha and genus Protaetia (Coleoptera: Scarabaeidae)","volume":"149","author":"Dutrillaux","year":"2016","journal-title":"Cytogenet. Genome Res."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"138","DOI":"10.1159\/000486441","article-title":"The relationship between the (in-)stability of NORs and their chromosomal location: The example of Cercopithecidae and a short review of other Primates","volume":"153","author":"Cacheux","year":"2017","journal-title":"Cytogenet. Genome Res."},{"key":"ref_38","unstructured":"Ashburner, M. (1989). Drosophila, a Laboratory Handbook, Cold Spring Harbor Laboratory Press."},{"key":"ref_39","doi-asserted-by":"crossref","unstructured":"Gu, S., Szafranski, P., Akdemir, Z.C., Yuan, B., Cooper, M.L., Magri\u00f1\u00e1, M.A., Bacino, C.A., Lalani, S.R., Breman, A.M., and Smith, J.L. (2016). Mechanisms for Complex Chromosomal Insertions. PLoS Genet., 12.","DOI":"10.1371\/journal.pgen.1006446"},{"key":"ref_40","unstructured":"Dutrillaux, A.-M., and Dutrillaux, B. (2022). Chromosome study of Lucanidae (Coleoptera), with emphasis on recurrent X-autosome rearrangements. Trends Entomol., in press."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"332","DOI":"10.1111\/j.1439-0469.2004.00267.x","article-title":"The evolutionary origin of a novel karyotype in Timarcha (Coleoptera, Chrysomelidae) and general trends of chromosome evolution in the genus","volume":"42","author":"Pons","year":"2004","journal-title":"J. Zool Syst. Evol. Res."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"195","DOI":"10.1159\/000321569","article-title":"Y-chromosome disomy and trisomy in Scarabaeid and Cerambycid beetles","volume":"132","author":"Dutrillaux","year":"2011","journal-title":"Cytogenet. Genome Res."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"54","DOI":"10.1139\/g68-008","article-title":"Selection for a supernumerary-chromosomein Dermestes maculatus (Coleoptera: Dermestidae)","volume":"10","author":"Shaw","year":"1968","journal-title":"Can. J. Genet. Cytol."}],"container-title":["Genes"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-4425\/14\/1\/150\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T18:00:28Z","timestamp":1760119228000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-4425\/14\/1\/150"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,1,5]]},"references-count":43,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2023,1]]}},"alternative-id":["genes14010150"],"URL":"https:\/\/doi.org\/10.3390\/genes14010150","relation":{},"ISSN":["2073-4425"],"issn-type":[{"value":"2073-4425","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,1,5]]}}}