@article {27, title = {Primary immunodeficiency diseases: Genomic approaches delineate heterogeneous Mendelian disorders.}, journal = {J Allergy Clin Immunol}, volume = {139}, year = {2017}, month = {2017 Jan}, pages = {232-245}, abstract = {

BACKGROUND: Primary immunodeficiency diseases (PIDDs) are clinically and genetically heterogeneous disorders thus far associated with mutations in more than 300 genes. The clinical phenotypes derived from distinct genotypes can overlap. Genetic etiology can be a prognostic indicator of disease severity and can influence treatment decisions.

OBJECTIVE: We sought to investigate the ability of whole-exome screening methods to detect disease-causing variants in patients with PIDDs.

METHODS: Patients with PIDDs from 278 families from 22 countries were investigated by using whole-exome sequencing. Computational copy number variant (CNV) prediction pipelines and an exome-tiling chromosomal microarray were also applied to identify intragenic CNVs. Analytic approaches initially focused on 475 known or candidate PIDD genes but were nonexclusive and further tailored based on clinical data, family history, and immunophenotyping.

RESULTS: A likely molecular diagnosis was achieved in 110 (40\%) unrelated probands. Clinical diagnosis was revised in about half (60/110) and management was directly altered in nearly a quarter (26/110) of families based on molecular findings. Twelve PIDD-causing CNVs were detected, including 7 smaller than 30~Kb that would not have been detected with conventional diagnostic CNV arrays.

CONCLUSION: This high-throughput genomic approach enabled detection of disease-related variants in unexpected genes; permitted detection of low-grade constitutional, somatic, and revertant mosaicism; and provided evidence of a mutational burden in mixed PIDD immunophenotypes.

}, keywords = {Adolescent, Adult, Aged, Child, Child, Preschool, DNA Copy Number Variations, Female, Genomics, High-Throughput Nucleotide Sequencing, Humans, Immunologic Deficiency Syndromes, Infant, Male, Middle Aged, Young Adult}, issn = {1097-6825}, doi = {10.1016/j.jaci.2016.05.042}, author = {Stray-Pedersen, Asbj{\o}rg and Sorte, Hanne S{\o}rmo and Samarakoon, Pubudu and Gambin, Tomasz and Chinn, Ivan K and Coban Akdemir, Zeynep H and Erichsen, Hans Christian and Forbes, Lisa R and Gu, Shen and Yuan, Bo and Jhangiani, Shalini N and Muzny, Donna M and R{\o}dningen, Olaug Kristin and Sheng, Ying and Nicholas, Sarah K and Noroski, Lenora M and Seeborg, Filiz O and Davis, Carla M and Canter, Debra L and Mace, Emily M and Vece, Timothy J and Allen, Carl E and Abhyankar, Harshal A and Boone, Philip M and Beck, Christine R and Wiszniewski, Wojciech and Fevang, B{\o}rre and Aukrust, P{\r a}l and Tj{\o}nnfjord, Geir E and Gedde-Dahl, Tobias and Hjorth-Hansen, Henrik and Dybedal, Ingunn and Nord{\o}y, Ingvild and J{\o}rgensen, Silje F and Abrahamsen, Tore G and {\O}verland, Torstein and Bechensteen, Anne Grete and Skogen, Vegard and Osnes, Liv T N and Kulseth, Mari Ann and Prescott, Trine E and Rustad, Cecilie F and Heimdal, Ketil R and Belmont, John W and Rider, Nicholas L and Chinen, Javier and Cao, Tram N and Smith, Eric A and Caldirola, Maria Soledad and Bezrodnik, Liliana and Lugo Reyes, Saul Oswaldo and Espinosa Rosales, Francisco J and Guerrero-Cursaru, Nina Denisse and Pedroza, Luis Alberto and Poli, Cecilia M and Franco, Jose L and Trujillo Vargas, Claudia M and Aldave Becerra, Juan Carlos and Wright, Nicola and Issekutz, Thomas B and Issekutz, Andrew C and Abbott, Jordan and Caldwell, Jason W and Bayer, Diana K and Chan, Alice Y and Aiuti, Alessandro and Cancrini, Caterina and Holmberg, Eva and West, Christina and Burstedt, Magnus and Karaca, Ender and Yesil, G{\"o}zde and Artac, Hasibe and Bayram, Yavuz and Atik, Mehmed Musa and Eldomery, Mohammad K and Ehlayel, Mohammad S and Jolles, Stephen and Flat{\o}, Berit and Bertuch, Alison A and Hanson, I Celine and Zhang, Victor W and Wong, Lee-Jun and Hu, Jianhong and Walkiewicz, Magdalena and Yang, Yaping and Eng, Christine M and Boerwinkle, Eric and Gibbs, Richard A and Shearer, William T and Lyle, Robert and Orange, Jordan S and Lupski, James R} } @article {9, title = {Identification of a RAI1-associated disease network through integration of exome sequencing, transcriptomics, and 3D genomics.}, journal = {Genome Med}, volume = {8}, year = {2016}, month = {2016 Nov 01}, pages = {105}, abstract = {

BACKGROUND: Smith-Magenis syndrome (SMS) is a developmental disability/multiple congenital anomaly disorder resulting from haploinsufficiency of RAI1. It is characterized by distinctive facial features, brachydactyly, sleep disturbances, and stereotypic behaviors.

METHODS: We investigated a cohort of 15 individuals with a clinical suspicion of SMS who showed neither deletion in the SMS critical region nor damaging variants in RAI1 using whole exome sequencing. A combination of network analysis (co-expression and biomedical text mining), transcriptomics, and circularized chromatin conformation capture (4C-seq) was applied to verify whether modified genes are part of the same disease network as known SMS-causing genes.

RESULTS: Potentially deleterious variants were identified in nine of these individuals using whole-exome sequencing. Eight of these changes affect KMT2D, ZEB2, MAP2K2, GLDC, CASK, MECP2, KDM5C, and POGZ, known to be associated with Kabuki syndrome 1, Mowat-Wilson syndrome, cardiofaciocutaneous syndrome, glycine encephalopathy, mental retardation and microcephaly with pontine and cerebellar hypoplasia, X-linked mental retardation 13, X-linked mental retardation Claes-Jensen type, and White-Sutton syndrome, respectively. The ninth individual carries a de novo variant in JAKMIP1, a regulator of neuronal translation that was recently found deleted in a patient with autism spectrum disorder. Analyses of co-expression and biomedical text mining suggest that these pathologies and SMS are part of the same disease network. Further support for this hypothesis was obtained from transcriptome profiling that showed that the expression levels of both Zeb2 and Map2k2 are perturbed in Rai1 mice. As an orthogonal approach to potentially contributory disease gene variants, we used chromatin conformation capture to reveal chromatin contacts between RAI1 and the loci flanking ZEB2 and GLDC, as well as between RAI1 and human orthologs of the genes that show perturbed expression in our Rai1 mouse model.

CONCLUSIONS: These holistic studies of RAI1 and its interactions allow insights into SMS and other disorders associated with intellectual disability and behavioral abnormalities. Our findings support a pan-genomic approach to the molecular diagnosis of a distinctive disorder.

}, keywords = {Animals, Embryo, Mammalian, Exome, Female, Gene Regulatory Networks, Genomics, Humans, Male, Mice, Mice, Inbred C57BL, Mice, Knockout, Mutation, Phenotype, Real-Time Polymerase Chain Reaction, Reverse Transcriptase Polymerase Chain Reaction, RNA, Messenger, Smith-Magenis Syndrome, Trans-Activators, Transcription Factors, Transcriptome}, issn = {1756-994X}, doi = {10.1186/s13073-016-0359-z}, author = {Loviglio, Maria Nicla and Beck, Christine R and White, Janson J and Leleu, Marion and Harel, Tamar and Guex, Nicolas and Niknejad, Anne and Bi, Weimin and Chen, Edward S and Crespo, Isaac and Yan, Jiong and Charng, Wu-Lin and Gu, Shen and Fang, Ping and Coban-Akdemir, Zeynep and Shaw, Chad A and Jhangiani, Shalini N and Muzny, Donna M and Gibbs, Richard A and Rougemont, Jacques and Xenarios, Ioannis and Lupski, James R and Reymond, Alexandre} } @article {170, title = {Alu-mediated diverse and complex pathogenic copy-number variants within human chromosome 17 at p13.3.}, journal = {Hum Mol Genet}, volume = {24}, year = {2015}, month = {2015 Jul 15}, pages = {4061-77}, abstract = {

Alu repetitive elements are known to be major contributors to genome instability by generating Alu-mediated copy-number variants (CNVs). Most of the reported Alu-mediated CNVs are simple deletions and duplications, and the mechanism underlying Alu-Alu-mediated rearrangement has been attributed to non-allelic homologous recombination (NAHR). Chromosome 17 at the p13.3 genomic region lacks extensive low-copy repeat architecture; however, it is highly enriched for Alu repetitive elements, with a fraction of 30\% of total sequence annotated in the human reference genome, compared with the 10\% genome-wide and 18\% on chromosome 17. We conducted mechanistic studies of the 17p13.3 CNVs by performing high-density oligonucleotide array comparative genomic hybridization, specifically interrogating the 17p13.3 region with \~{}150 bp per probe density; CNV breakpoint junctions were mapped to nucleotide resolution by polymerase chain reaction and Sanger sequencing. Studied rearrangements include 5 interstitial deletions, 14 tandem duplications, 7 terminal deletions and 13 complex genomic rearrangements (CGRs). Within the 17p13.3 region, Alu-Alu-mediated rearrangements were identified in 80\% of the interstitial deletions, 46\% of the tandem duplications and 50\% of the CGRs, indicating that this mechanism was a major contributor for formation of breakpoint junctions. Our studies suggest that Alu repetitive elements facilitate formation of non-recurrent CNVs, CGRs and other structural aberrations of chromosome 17 at p13.3. The common observation of Alu-mediated rearrangement in CGRs and breakpoint junction sequences analysis further demonstrates that this type of mechanism is unlikely attributed to NAHR, but rather may be due to a recombination-coupled DNA replicative repair process.

}, keywords = {Alleles, Alu Elements, Base Sequence, Chromosomes, Human, Pair 17, Comparative Genomic Hybridization, DNA Copy Number Variations, Female, Gene Duplication, Gene Rearrangement, Genome, Human, Genomic Instability, Genomics, Homologous Recombination, Humans, Male, Molecular Sequence Data, Segmental Duplications, Genomic, Sequence Deletion}, issn = {1460-2083}, doi = {10.1093/hmg/ddv146}, author = {Gu, Shen and Yuan, Bo and Campbell, Ian M and Beck, Christine R and Carvalho, Claudia M B and Nagamani, Sandesh C S and Erez, Ayelet and Patel, Ankita and Bacino, Carlos A and Shaw, Chad A and Stankiewicz, Pawe{\l} and Cheung, Sau Wai and Bi, Weimin and Lupski, James R} } @article {120, title = {Nonrecurrent 17p11.2p12 Rearrangement Events that Result in Two Concomitant Genomic Disorders: The PMP22-RAI1 Contiguous Gene Duplication Syndrome.}, journal = {Am J Hum Genet}, volume = {97}, year = {2015}, month = {2015 Nov 05}, pages = {691-707}, abstract = {

The genomic duplication associated with Potocki-Lupski syndrome (PTLS) maps in close proximity to the duplication associated with Charcot-Marie-Tooth disease type 1A (CMT1A). PTLS is characterized by hypotonia, failure to thrive, reduced body weight, intellectual disability, and autistic features. CMT1A is a common autosomal dominant distal symmetric peripheral polyneuropathy. The key dosage-sensitive genes RAI1 and PMP22 are respectively associated with PTLS and CMT1A. Recurrent duplications accounting for the majority of subjects with these conditions are mediated by nonallelic homologous recombination between distinct low-copy repeat (LCR) substrates. The LCRs flanking a contiguous genomic interval encompassing both RAI1 and PMP22 do not share extensive homology; thus, duplications encompassing both loci are rare and potentially generated by a different mutational mechanism. We characterized genomic rearrangements that simultaneously duplicate PMP22 and RAI1, including nine potential complex genomic rearrangements, in 23 subjects by high-resolution array comparative genomic hybridization and breakpoint junction sequencing. Insertions and microhomologies were found at the breakpoint junctions, suggesting potential replicative mechanisms for rearrangement formation. At the breakpoint junctions of these nonrecurrent rearrangements, enrichment of repetitive DNA sequences was observed, indicating that they might predispose to genomic instability and rearrangement. Clinical evaluation revealed blended PTLS and CMT1A phenotypes with a potential earlier onset of neuropathy. Moreover, additional clinical findings might be observed due to the extra duplicated material included in the rearrangements. Our genomic analysis suggests replicative mechanisms as a predominant mechanism underlying PMP22-RAI1 contiguous gene duplications and provides further evidence supporting the role of complex genomic architecture in genomic instability.

}, keywords = {Abnormalities, Multiple, Charcot-Marie-Tooth Disease, Child, Child, Preschool, Chromosome Disorders, Chromosome Duplication, Chromosomes, Human, Pair 17, Comparative Genomic Hybridization, Female, Follow-Up Studies, Gene Duplication, Gene Rearrangement, Genome, Human, Genomics, Humans, Infant, Male, Models, Genetic, Myelin Proteins, Phenotype, Prognosis, Recombination, Genetic, Transcription Factors}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2015.10.003}, author = {Yuan, Bo and Harel, Tamar and Gu, Shen and Liu, Pengfei and Burglen, Lydie and Chantot-Bastaraud, Sandra and Gelowani, Violet and Beck, Christine R and Carvalho, Claudia M B and Cheung, Sau Wai and Coe, Andrew and Malan, Val{\'e}rie and Munnich, Arnold and Magoulas, Pilar L and Potocki, Lorraine and Lupski, James R} }