Gibbon genome and the fast karyotype evolution of small apes

Gibbons are small arboreal apes that display an accelerated rate of evolutionary chromosomal rearrangement and occupy a key node in the primate phylogeny between Old World monkeys and great apes. Here we present the assembly and analysis of a northern white-cheeked gibbon (Nomascus leucogenys) genome. We describe the propensity for a gibbon-specific retrotransposon (LAVA) to insert into chromosome segregation genes and alter transcription by providing a premature termination site, suggesting a possible molecular mechanism for the genome plasticity of the gibbon lineage. We further show that the gibbon genera (Nomascus, Hylobates, Hoolock and Symphalangus) experienced a near-instantaneous radiation 5 million years ago, coincident with major geographical changes in southeast Asia that caused cycles of habitat compression and expansion. Finally, we identify signatures of positive selection in genes important for forelimb development (TBX5) and connective tissues (COL1A1) that may have been involved in the adaptation of gibbons to their arboreal habitat.The gibbon genome project was funded by the National Human Genome Research Institute (NHGRI) including grants U54 HG003273 (R.A.G.) and U54 HG003079 (R.K.W.) with further support from National Institutes of Health NIH/NIAAA P30 AA019355 and NIH/NCRR P51 RR000163 (L.C.), R01_HG005226 (J.D.W., M.F.H.), NIH P30CA006973 (S.J.W.), a fellowship from the National Library of Medicine Biomedical Informatics Research Training Program (N.H.L.), R01 GM59290 (M.A.B.) and U41 HG007497-01 (M.A.B, M.K.K.), R01 MH081203 (J.M.S.), HG002385 (E.E.E.), National Science Foundation (NSF) CNS-1126739 (B.U., M.A.B., M.K.K.) and DBI-0845494 (M.W.H.), PRIN 2012 (M.R.), Futuro in ricerca 2010 RBFR103CE3 (M.V.), ERC Starting Grant (260372) and MICINN (Spain) BFU2011-28549 (T.M.-B.), grant of the Ministry of National Education, CNCS – UEFISCDI, project number PN-II-ID-PCE-2012-4-0090 (A.D.), grant of the Deutsche Forschungsgemeinschaft SCHU1014/8-1 (G.G.S.), ERC Starting and Advanced Grant and EMBO Young Investigator Award (Z.I., N.V.F.), ERC Starting Grant and EMBO Young Investigator Award (D.T.O.), Commonwealth Scholarship Commission (M.C.W.). E.E.E. is an investigator of the Howard Hughes Medical Institute. We acknowledge the contributions of the staff of the HGSC, including the operations team: H. Dinh, S. Jhangiani V. Korchina, C. Kovar; the library team: K. Blankenburg, L. Pu, S. Vattathil; the assembly team: D. Rio-Deiros, H. Jiang; the submissions team: M. Batterton, D. Kalra, K. Wilczek-Boney, W. Hale, G. Fowler, J. Zhang; the quality control team: P. Aqrawi, S. Gross, V. Joshi, J. Santibanez; and the sequence production team: U. Anosike, C. Babu, D. Bandaranaike, B. Beltran, D. Berhane-Mersha, C. Bickham, T. Bolden, M. Dao, M. Davila, L. Davy-Carroll, S. Denson, P. Fernando, C. Francis, R. Garcia III, B. Hollins, B. Johnson, J. Jones, J. Kalu, N. Khan, B. Leal, F. Legall III, Y. Liu, J. Lopez, R. Mata, M. Obregon, C. Onwere, A. Parra, Y. Perez, A. Perez, C. Pham, J. Quiroz, S. Ruiz, M. Scheel, D. Simmons, I. Sisson, J. Tisius, G. Toledanes, R. Varghese, V. Vee, D. Walker, C. White, A. Williams, R. Wright, T. Attaway, T. Garrett, C. Mercado, N. Ngyen, H. Paul and Z. Trejos. We thank Z. Ivics for providing some of the reagents. We additionally acknowledge the Production Sequencing Group at The Genome Institute. Wellcome Trust (grant numbers WT095908 and WT098051), NHGRI (U41HG007234) and European Molecular Biology Laboratory. For the production of next-generation sequences, we acknowledge the Massively Parallel Sequencing Shared Resources (MPSSR) at OHSU, the National Center of Genomic Analyses (CNAG) (Barcelona, Spain), the University of Arizona Genetics Core (UAGC), and the UCSF sequencing core. We also acknowledge the Louisiana Optical Network Institute (LONI). We thank the Gibbon Conservation Center and the Fort Wayne Children’s Zoo for providing the gibbon samples. The MAKER annotation pipeline is supported by NSF IOS-1126998.We thank T. Brown for proofreading and editing the manuscript

Coherent somatic mutation in autoimmune disease.

Many aspects of autoimmune disease are not well understood, including the specificities of autoimmune targets, and patterns of co-morbidity and cross-heritability across diseases. Prior work has provided evidence that somatic mutation caused by gene conversion and deletion at segmentally duplicated loci is relevant to several diseases. Simple tandem repeat (STR) sequence is highly mutable, both somatically and in the germ-line, and somatic STR mutations are observed under inflammation.Protein-coding genes spanning STRs having markers of mutability, including germ-line variability, high total length, repeat count and/or repeat similarity, are evaluated in the context of autoimmunity. For the initiation of autoimmune disease, antigens whose autoantibodies are the first observed in a disease, termed primary autoantigens, are informative. Three primary autoantigens, thyroid peroxidase (TPO), phogrin (PTPRN2) and filaggrin (FLG), include STRs that are among the eleven longest STRs spanned by protein-coding genes. This association of primary autoantigens with long STR sequence is highly significant (p<3.0x10(-7)). Long STRs occur within twenty genes that are associated with sixteen common autoimmune diseases and atherosclerosis. The repeat within the TTC34 gene is an outlier in terms of length and a link with systemic lupus erythematosus is proposed.The results support the hypothesis that many autoimmune diseases are triggered by immune responses to proteins whose DNA sequence mutates somatically in a coherent, consistent fashion. Other autoimmune diseases may be caused by coherent somatic mutations in immune cells. The coherent somatic mutation hypothesis has the potential to be a comprehensive explanation for the initiation of many autoimmune diseases