@article {515, title = {Clinical exome sequencing reveals locus heterogeneity and phenotypic variability of cohesinopathies.}, journal = {Genet Med}, volume = {21}, year = {2019}, month = {2019 03}, pages = {663-675}, abstract = {

PURPOSE: Defects in the cohesin pathway are associated with cohesinopathies, notably Cornelia de Lange syndrome (CdLS). We aimed to delineate pathogenic variants~in known and candidate cohesinopathy genes from a clinical exome perspective.

METHODS: We retrospectively studied patients referred for clinical exome sequencing (CES, N = 10,698). Patients with causative variants in novel or recently described cohesinopathy genes were enrolled for phenotypic characterization.

RESULTS: Pathogenic or likely pathogenic single-nucleotide and insertion/deletion variants (SNVs/indels) were identified in established disease genes including NIPBL (N = 5), SMC1A (N = 14), SMC3 (N = 4), RAD21 (N = 2), and HDAC8 (N = 8). The phenotypes in this genetically defined cohort skew towards the mild end of CdLS spectrum as compared with phenotype-driven cohorts. Candidate or recently reported cohesinopathy genes were supported by de novo SNVs/indels in STAG1 (N = 3), STAG2 (N = 5), PDS5A (N = 1), and WAPL (N = 1), and one inherited SNV in PDS5A. We also identified copy-number deletions affecting STAG1 (two de novo, one of unknown inheritance) and STAG2 (one of unknown inheritance). Patients with STAG1 and STAG2 variants presented with overlapping features yet without characteristic facial features of CdLS.

CONCLUSION: CES effectively identified disease-causing alleles at the mild end of the cohensinopathy spectrum and enabled characterization of candidate disease genes.

}, keywords = {Adolescent, Alleles, Antigens, Nuclear, Biological Variation, Population, Carrier Proteins, Cell Cycle Proteins, Child, Child, Preschool, Chromosomal Proteins, Non-Histone, Cohort Studies, De Lange Syndrome, Exome, Female, Gene Frequency, Genetic Heterogeneity, Humans, INDEL Mutation, Male, Mutation, Nuclear Proteins, Phenotype, Polymorphism, Single Nucleotide, Proto-Oncogene Proteins, Retrospective Studies, Whole Exome Sequencing}, issn = {1530-0366}, doi = {10.1038/s41436-018-0085-6}, author = {Yuan, Bo and Neira, Juanita and Pehlivan, Davut and Santiago-Sim, Teresa and Song, Xiaofei and Rosenfeld, Jill and Posey, Jennifer E and Patel, Vipulkumar and Jin, Weihong and Adam, Margaret P and Baple, Emma L and Dean, John and Fong, Chin-To and Hickey, Scott E and Hudgins, Louanne and Leon, Eyby and Madan-Khetarpal, Suneeta and Rawlins, Lettie and Rustad, Cecilie F and Stray-Pedersen, Asbj{\o}rg and Tveten, Kristian and Wenger, Olivia and Diaz, Jullianne and Jenkins, Laura and Martin, Laura and McGuire, Marianne and Pietryga, Marguerite and Ramsdell, Linda and Slattery, Leah and Abid, Farida and Bertuch, Alison A and Grange, Dorothy and Immken, LaDonna and Schaaf, Christian P and Van Esch, Hilde and Bi, Weimin and Cheung, Sau Wai and Breman, Amy M and Smith, Janice L and Shaw, Chad and Crosby, Andrew H and Eng, Christine and Yang, Yaping and Lupski, James R and Xiao, Rui and Liu, Pengfei} } @article {673, title = {Reanalysis of Clinical Exome Sequencing Data.}, journal = {N Engl J Med}, volume = {380}, year = {2019}, month = {2019 06 20}, pages = {2478-2480}, keywords = {Exome, Genetic Diseases, Inborn, Genetic Testing, Humans, Mutation, Phenotype, Sequence Analysis, DNA, Whole Exome Sequencing}, issn = {1533-4406}, doi = {10.1056/NEJMc1812033}, author = {Liu, Pengfei and Meng, Linyan and Normand, Elizabeth A and Xia, Fan and Song, Xiaofei and Ghazi, Andrew and Rosenfeld, Jill and Magoulas, Pilar L and Braxton, Alicia and Ward, Patricia and Dai, Hongzheng and Yuan, Bo and Bi, Weimin and Xiao, Rui and Wang, Xia and Chiang, Theodore and Vetrini, Francesco and He, Weimin and Cheng, Hanyin and Dong, Jie and Gijavanekar, Charul and Benke, Paul J and Bernstein, Jonathan A and Eble, Tanya and Eroglu, Yasemen and Erwin, Deanna and Escobar, Luis and Gibson, James B and Gripp, Karen and Kleppe, Soledad and Koenig, Mary K and Lewis, Andrea M and Natowicz, Marvin and Mancias, Pedro and Minor, LaKeesha and Scaglia, Fernando and Schaaf, Christian P and Streff, Haley and Vernon, Hilary and Uhles, Crescenda L and Zackai, Elaine H and Wu, Nan and Sutton, V Reid and Beaudet, Arthur L and Muzny, Donna and Gibbs, Richard A and Posey, Jennifer E and Lalani, Seema and Shaw, Chad and Eng, Christine M and Lupski, James R and Yang, Yaping} } @article {526, title = {The coexistence of copy number variations (CNVs) and single nucleotide polymorphisms (SNPs) at a locus can result in distorted calculations of the significance in associating SNPs to disease.}, journal = {Hum Genet}, volume = {137}, year = {2018}, month = {2018 Jul}, pages = {553-567}, abstract = {

With the recent advance in genome-wide association studies (GWAS), disease-associated single nucleotide polymorphisms (SNPs) and copy number variants (CNVs) have been extensively reported. Accordingly, the issue of incorrect identification of recombination events that can induce the distortion of multi-allelic or hemizygous variants has received more attention. However, the potential distorted calculation bias or significance of a detected association in a GWAS due to the coexistence of CNVs and SNPs in the same genomic region may remain under-recognized. Here we performed the association study within a congenital scoliosis (CS) cohort whose genetic etiology was recently elucidated as a compound inheritance model, including mostly one rare variant deletion CNV null allele and one common variant non-coding hypomorphic haplotype of the TBX6 gene. We demonstrated that the existence of a deletion in TBX6 led to an overestimation of the contribution of the SNPs on the hypomorphic allele. Furthermore, we generalized a model to explain the calculation bias, or distorted significance calculation for an association study, that can be {\textquoteright}induced{\textquoteright} by CNVs at a locus. Meanwhile, overlapping between the disease-associated SNPs from published GWAS and common CNVs (overlap 10\%) and pathogenic/likely pathogenic CNVs (overlap 99.69\%) was significantly higher than the random distribution (p < 1 {\texttimes} 10 and p = 0.034, respectively), indicating that such co-existence of CNV and SNV alleles might generally influence data interpretation and potential outcomes of a GWAS. We also verified and assessed the influence of colocalizing CNVs to the detection sensitivity of disease-associated SNP variant alleles in another adolescent idiopathic scoliosis (AIS) genome-wide association study. We proposed that detecting co-existent CNVs when evaluating the association signals between SNPs and disease traits could improve genetic model analyses and better integrate GWAS with robust Mendelian principles.

}, keywords = {Adolescent, Congenital Abnormalities, DNA Copy Number Variations, Female, Genetic Predisposition to Disease, Genome, Human, Genome-Wide Association Study, Genomics, Genotype, Haplotypes, Humans, Phenotype, Polymorphism, Single Nucleotide, Scoliosis}, issn = {1432-1203}, doi = {10.1007/s00439-018-1910-3}, author = {Liu, Jiaqi and Zhou, Yangzhong and Liu, Sen and Song, Xiaofei and Yang, Xin-Zhuang and Fan, Yanhui and Chen, Weisheng and Akdemir, Zeynep Coban and Yan, Zihui and Zuo, Yuzhi and Du, Renqian and Liu, Zhenlei and Yuan, Bo and Zhao, Sen and Liu, Gang and Chen, Yixin and Zhao, Yanxue and Lin, Mao and Zhu, Qiankun and Niu, Yuchen and Liu, Pengfei and Ikegawa, Shiro and Song, You-Qiang and Posey, Jennifer E and Qiu, Guixing and Zhang, Feng and Wu, Zhihong and Lupski, James R and Wu, Nan} } @article {344, title = {Complex inheritance of ABCA4 disease: four mutations in a family with multiple macular phenotypes.}, journal = {Hum Genet}, volume = {135}, year = {2016}, month = {2016 Jan}, pages = {9-19}, abstract = {

Over 800 mutations in the ABCA4 gene cause autosomal recessive Stargardt disease. Due to extensive genetic heterogeneity, observed variant-associated phenotypes can manifest tremendous variability of expression. Furthermore, the high carrier frequency of pathogenic ABCA4 alleles in the general population (~1:20) often results in pseudo-dominant inheritance patterns further complicating the diagnosis and characterization of affected individuals. This study describes a genotype/phenotype analysis of an unusual family with multiple macular disease phenotypes spanning across two generations and segregating four distinct ABCA4 mutant alleles. Complete sequencing of ABCA4 discovered two known missense mutations, p.C54Y and p.G1961E. Array comparative genomic hybridization revealed a large novel deletion combined with a small insertion, c.6148-698_c.6670del/insTGTGCACCTCCCTAG, and complete sequencing of the entire ABCA4 genomic locus uncovered a new deep intronic variant, c.302+68C>T. Patients with the p.G1961E mutation had the mildest, confined maculopathy phenotype with peripheral flecks while those with all other mutant allele combinations exhibited a more advanced stage of generalized retinal and choriocapillaris atrophy. This family epitomizes the clinical and genetic complexity of ABCA4-associated diseases. It contained variants from all classes of mutations, in the coding region, deep intronic, both single nucleotide variants and copy number variants that accounted for varying phenotypes segregating in an apparent dominant fashion. Unequivocally defining disease-associated alleles in the ABCA4 locus requires a multifaceted approach that includes advanced mutation detection methods and a thorough analysis of clinical phenotypes.

}, keywords = {Adult, Aged, ATP-Binding Cassette Transporters, Comparative Genomic Hybridization, DNA Copy Number Variations, Electroretinography, Female, High-Throughput Nucleotide Sequencing, Humans, Macula Lutea, Macular Degeneration, Male, Middle Aged, Mutation, Pedigree, Phenotype}, issn = {1432-1203}, doi = {10.1007/s00439-015-1605-y}, author = {Lee, Winston and Xie, Yajing and Zernant, Jana and Yuan, Bo and Bearelly, Srilaxmi and Tsang, Stephen H and Lupski, James R and Allikmets, Rando} } @article {21, title = {Recurrent De Novo and Biallelic Variation of ATAD3A, Encoding a Mitochondrial Membrane Protein, Results in Distinct Neurological Syndromes.}, journal = {Am J Hum Genet}, volume = {99}, year = {2016}, month = {2016 Oct 06}, pages = {831-845}, abstract = {

ATPase family AAA-domain containing protein 3A (ATAD3A) is a nuclear-encoded mitochondrial membrane protein implicated in mitochondrial dynamics, nucleoid organization, protein translation, cell growth, and cholesterol metabolism. We identified a recurrent de novo ATAD3A c.1582C>T (p.Arg528Trp) variant by whole-exome sequencing (WES) in five unrelated individuals with a core phenotype of global developmental delay, hypotonia, optic atrophy, axonal neuropathy, and hypertrophic cardiomyopathy. We also describe two families with biallelic variants in ATAD3A, including a homozygous variant in two siblings, and biallelic ATAD3A deletions mediated by nonallelic homologous recombination (NAHR) between ATAD3A and gene family members ATAD3B and ATAD3C. Tissue-specific overexpression of bor, the Drosophila mutation homologous to the human c.1582C>T (p.Arg528Trp) variant, resulted in a dramatic decrease in mitochondrial content, aberrant mitochondrial morphology, and increased autophagy. Homozygous null bor larvae showed a significant decrease of mitochondria, while overexpression of bor resulted in larger, elongated mitochondria. Finally, fibroblasts of an affected individual exhibited increased mitophagy. We conclude that the p.Arg528Trp variant functions through a dominant-negative mechanism that results in small mitochondria that trigger mitophagy, resulting in a reduction in mitochondrial content. ATAD3A variation represents an additional link between mitochondrial dynamics and recognizable neurological syndromes, as seen with MFN2, OPA1, DNM1L, and STAT2 mutations.

}, keywords = {Adenosine Triphosphatases, Adult, Alleles, Animals, ATPases Associated with Diverse Cellular Activities, Axons, Cardiomyopathies, Child, Child, Preschool, Developmental Disabilities, DNA Copy Number Variations, Drosophila melanogaster, Female, Fibroblasts, Homozygote, Humans, Infant, Infant, Newborn, Male, Membrane Proteins, Mitochondria, Mitochondrial Proteins, Muscle Hypotonia, Muscles, Mutation, Nervous System Diseases, Neurons, Optic Atrophy, Phenotype, Polymorphism, Single Nucleotide, Syndrome, Young Adult}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2016.08.007}, author = {Harel, Tamar and Yoon, Wan Hee and Garone, Caterina and Gu, Shen and Coban-Akdemir, Zeynep and Eldomery, Mohammad K and Posey, Jennifer E and Jhangiani, Shalini N and Rosenfeld, Jill A and Cho, Megan T and Fox, Stephanie and Withers, Marjorie and Brooks, Stephanie M and Chiang, Theodore and Duraine, Lita and Erdin, Serkan and Yuan, Bo and Shao, Yunru and Moussallem, Elie and Lamperti, Costanza and Donati, Maria A and Smith, Joshua D and McLaughlin, Heather M and Eng, Christine M and Walkiewicz, Magdalena and Xia, Fan and Pippucci, Tommaso and Magini, Pamela and Seri, Marco and Zeviani, Massimo and Hirano, Michio and Hunter, Jill V and Srour, Myriam and Zanigni, Stefano and Lewis, Richard Alan and Muzny, Donna M and Lotze, Timothy E and Boerwinkle, Eric and Gibbs, Richard A and Hickey, Scott E and Graham, Brett H and Yang, Yaping and Buhas, Daniela and Martin, Donna M and Potocki, Lorraine and Graziano, Claudio and Bellen, Hugo J and Lupski, James R} } @article {167, title = {Germline PRKACA amplification causes variable phenotypes that may depend on the extent of the genomic defect: molecular mechanisms and clinical presentations.}, journal = {Eur J Endocrinol}, volume = {172}, year = {2015}, month = {2015 06}, pages = {803-11}, abstract = {

OBJECTIVE: We have recently reported five patients with bilateral adrenocortical hyperplasia (BAH) and Cushing{\textquoteright}s syndrome (CS) caused by constitutive activation of the catalytic subunit of protein kinase A (PRKACA). By doing new in-depth analysis of their cytogenetic abnormality, we attempted a better genotype-phenotype correlation of their PRKACA amplification.

DESIGN: This study is a case series.

METHODS: Molecular cytogenetic, genomic, clinical, and histopathological analyses were performed in five patients with CS.

RESULTS: Reinvestigation of the defects of previously described patients by state-of-the-art molecular cytogenetics showed complex genomic rearrangements in the chromosome 19p13.2p13.12 locus, resulting in copy number gains encompassing the entire PRKACA gene; three patients (one sporadic case and two related cases) were observed with gains consistent with duplications, while two sporadic patients were observed with gains consistent with triplications. Although all five patients presented with ACTH-independent CS, the three sporadic patients had micronodular BAH and underwent bilateral adrenalectomy in early childhood, whereas the two related patients, a mother and a son, presented with macronodular BAH as adults. In at least one patient, PRKACA triplication was associated with a more severe phenotype.

CONCLUSIONS: Constitutional chromosomal PRKACA gene amplification is a recently identified genetic defect associated with CS, a trait that may be inherited in an autosomal dominant manner or occur de novo. Genomic rearrangements can be complex and can result in different copy number states of dosage-sensitive genes, e.g., duplication and triplication. PRKACA amplification can lead to variable phenotypes clinically and pathologically, both micro- and macro-nodular BAH, the latter of which we speculate may depend on the extent of amplification.

}, keywords = {Adrenal Glands, Adrenalectomy, Adult, Child, Child, Preschool, Cushing Syndrome, Cyclic AMP-Dependent Protein Kinase Catalytic Subunits, DNA Copy Number Variations, Female, Gene Amplification, Humans, Hyperplasia, Male, Phenotype, Young Adult}, issn = {1479-683X}, doi = {10.1530/EJE-14-1154}, author = {Lodish, Maya B and Yuan, Bo and Levy, Isaac and Braunstein, Glenn D and Lyssikatos, Charalampos and Salpea, Paraskevi and Szarek, Eva and Karageorgiadis, Alexander S and Belyavskaya, Elena and Raygada, Margarita and Faucz, Fabio Rueda and Izzat, Louise and Brain, Caroline and Gardner, James and Quezado, Martha and Carney, J Aidan and Lupski, James R and Stratakis, Constantine A} } @article {198, title = {Global transcriptional disturbances underlie Cornelia de Lange syndrome and related phenotypes.}, journal = {J Clin Invest}, volume = {125}, year = {2015}, month = {2015 Feb}, pages = {636-51}, abstract = {

Cornelia de Lange syndrome (CdLS) is a genetically heterogeneous disorder that presents with extensive phenotypic variability, including facial dysmorphism, developmental delay/intellectual disability (DD/ID), abnormal extremities, and hirsutism. About 65\% of patients harbor mutations in genes that encode subunits or regulators of the cohesin complex, including NIPBL, SMC1A, SMC3, RAD21, and HDAC8. Wiedemann-Steiner syndrome (WDSTS), which shares CdLS phenotypic features, is caused by mutations in lysine-specific methyltransferase 2A (KMT2A). Here, we performed whole-exome sequencing (WES) of 2 male siblings clinically diagnosed with WDSTS; this revealed a hemizygous, missense mutation in SMC1A that was predicted to be deleterious. Extensive clinical evaluation and WES of 32 Turkish patients clinically diagnosed with CdLS revealed the presence of a de novo heterozygous nonsense KMT2A mutation in 1 patient without characteristic WDSTS features. We also identified de novo heterozygous mutations in SMC3 or SMC1A that affected RNA splicing in 2 independent patients with combined CdLS and WDSTS features. Furthermore, in families from 2 separate world populations segregating an autosomal-recessive disorder with CdLS-like features, we identified homozygous mutations in TAF6, which encodes a core transcriptional regulatory pathway component. Together, our data, along with recent transcriptome studies, suggest that CdLS and related phenotypes may be "transcriptomopathies" rather than cohesinopathies.

}, keywords = {Adolescent, Adult, Cell Cycle Proteins, Child, Child, Preschool, Chondroitin Sulfate Proteoglycans, Chromosomal Proteins, Non-Histone, Codon, Nonsense, De Lange Syndrome, Exome, Exonucleases, Gene Expression Profiling, Gene Expression Regulation, Genome-Wide Association Study, Heterozygote, Histone Deacetylases, Histone-Lysine N-Methyltransferase, Humans, Infant, Male, Myeloid-Lymphoid Leukemia Protein, Phenotype, Proteins, Repressor Proteins, Transcriptome}, issn = {1558-8238}, doi = {10.1172/JCI77435}, author = {Yuan, Bo and Pehlivan, Davut and Karaca, Ender and Patel, Nisha and Charng, Wu-Lin and Gambin, Tomasz and Gonzaga-Jauregui, Claudia and Sutton, V Reid and Yesil, G{\"o}zde and Bozdogan, Sevcan Tug and Tos, Tulay and Koparir, Asuman and Koparir, Erkan and Beck, Christine R and Gu, Shen and Aslan, Huseyin and Yuregir, Ozge Ozalp and Al Rubeaan, Khalid and Alnaqeb, Dhekra and Alshammari, Muneera J and Bayram, Yavuz and Atik, Mehmed M and Aydin, Hatip and Geckinli, B Bilge and Seven, Mehmet and Ulucan, Hakan and Fenercioglu, Elif and Ozen, Mustafa and Jhangiani, Shalini and Muzny, Donna M and Boerwinkle, Eric and Tuysuz, Beyhan and Alkuraya, Fowzan S and Gibbs, Richard A and Lupski, James R} } @article {216, title = {New mutations in the RAB28 gene in 2 Spanish families with cone-rod dystrophy.}, journal = {JAMA Ophthalmol}, volume = {133}, year = {2015}, month = {2015 Feb}, pages = {133-9}, abstract = {

IMPORTANCE: The families evaluated in this study represent the second report of cone-rod dystrophy (CRD) cases caused by mutations in RAB28, a recently discovered gene associated with CRD.

OBJECTIVE: To determine the disease-causing gene in 2 families of Spanish descent presenting with CRD who do not have ABCA4 mutations.

DESIGN, SETTING, AND PARTICIPANTS: Molecular genetics and observational case studies of 2 families, each with 1 affected proband with CRD and 3 or 5 unaffected family members. The affected individual from each family received a complete ophthalmic examination including assessment of refractive errors and best-corrected visual acuity, biomicroscopy, color fundus photography, electroretinography analysis, and visual-evoked potential analysis. After complete sequencing of the ABCA4 gene with negative results, the screening for disease-causing mutations was performed by whole-exome sequencing. Possible disease-associated variants were determined by filtering based on minor allele frequency, predicted pathogenicity, and segregation analysis in all family members.

MAIN OUTCOMES AND MEASURES: The appearance of the macula was evaluated by clinical examination, fundus photography, and fundus autofluorescence imaging, and visual function was assessed by electroretinography. Disease-causing mutations were assessed by sequence analyses.

RESULTS: Ophthalmologic findings included markedly reduced visual acuity, bull{\textquoteright}s eye maculopathy, foveal hyperpigmentation, peripapillary atrophy, dyschromatopsia, extinguished photopic responses, and reduced scotopic responses observed on electroretinography consistent with the CRD phenotype often associated with ABCA4 mutations. Although no ABCA4 mutations were detected in either patient, whole-exome sequencing analysis identified 2 new homozygous mutations in the recently described RAB28 gene, the c.172 + 1G>C splice site variant in IVS2 and the missense c.T651G:p.C217W substitution. Both variants were determined as deleterious by predictive programs and were segregated with the disease in both families. Sequencing of 107 additional patients of Spanish descent with CRD did not reveal other cases with RAB28 mutations.

CONCLUSIONS AND RELEVANCE: Deleterious mutations in RAB28 result in a classic CRD phenotype and are an infrequent cause of CRD in the Spanish population.

}, keywords = {Adolescent, Adult, Child, Diagnosis, Differential, DNA Mutational Analysis, Female, Follow-Up Studies, Genetic Predisposition to Disease, Hispanic Americans, Humans, Male, Microscopy, Acoustic, Mutation, Pedigree, Phenotype, rab GTP-Binding Proteins, Retinitis Pigmentosa, Retrospective Studies, Young Adult}, issn = {2168-6173}, doi = {10.1001/jamaophthalmol.2014.4266}, author = {Riveiro-{\'A}lvarez, Rosa and Xie, Yajing Angela and L{\'o}pez-Mart{\'\i}nez, Miguel-{\'A}ngel and Gambin, Tomasz and P{\'e}rez-Carro, Raquel and {\'A}vila-Fern{\'a}ndez, Almudena and L{\'o}pez-Molina, Mar{\'\i}a-Isabel and Zernant, Jana and Jhangiani, Shalini and Muzny, Donna and Yuan, Bo and Boerwinkle, Eric and Gibbs, Richard and Lupski, James R and Ayuso, Carmen and Allikmets, Rando} } @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} } @article {207, title = {Gigantism and acromegaly due to Xq26 microduplications and GPR101 mutation.}, journal = {N Engl J Med}, volume = {371}, year = {2014}, month = {2014 Dec 18}, pages = {2363-74}, abstract = {

BACKGROUND: Increased secretion of growth hormone leads to gigantism in children and acromegaly in adults; the genetic causes of gigantism and acromegaly are poorly understood.

METHODS: We performed clinical and genetic studies of samples obtained from 43 patients with gigantism and then sequenced an implicated gene in samples from 248 patients with acromegaly.

RESULTS: We observed microduplication on chromosome Xq26.3 in samples from 13 patients with gigantism; of these samples, 4 were obtained from members of two unrelated kindreds, and 9 were from patients with sporadic cases. All the patients had disease onset during early childhood. Of the patients with gigantism who did not carry an Xq26.3 microduplication, none presented before the age of 5 years. Genomic characterization of the Xq26.3 region suggests that the microduplications are generated during chromosome replication and that they contain four protein-coding genes. Only one of these genes, GPR101, which encodes a G-protein-coupled receptor, was overexpressed in patients{\textquoteright} pituitary lesions. We identified a recurrent GPR101 mutation (p.E308D) in 11 of 248 patients with acromegaly, with the mutation found mostly in tumors. When the mutation was transfected into rat GH3 cells, it led to increased release of growth hormone and proliferation of growth hormone-producing cells.

CONCLUSIONS: We describe a pediatric disorder (which we have termed X-linked acrogigantism [X-LAG]) that is caused by an Xq26.3 genomic duplication and is characterized by early-onset gigantism resulting from an excess of growth hormone. Duplication of GPR101 probably causes X-LAG. We also found a recurrent mutation in GPR101 in some adults with acromegaly. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development and others.).

}, keywords = {Acromegaly, Adolescent, Adult, Age of Onset, Child, Child, Preschool, Chromosome Duplication, Chromosomes, Human, X, Female, Gigantism, Human Growth Hormone, Humans, Infant, Male, Mutation, Phenotype, Protein Conformation, Receptors, G-Protein-Coupled}, issn = {1533-4406}, doi = {10.1056/NEJMoa1408028}, author = {Trivellin, Giampaolo and Daly, Adrian F and Faucz, Fabio R and Yuan, Bo and Rostomyan, Liliya and Larco, Darwin O and Schernthaner-Reiter, Marie Helene and Szarek, Eva and Leal, Let{\'\i}cia F and Caberg, Jean-Hubert and Castermans, Emilie and Villa, Chiara and Dimopoulos, Aggeliki and Chittiboina, Prashant and Xekouki, Paraskevi and Shah, Nalini and Metzger, Daniel and Lysy, Philippe A and Ferrante, Emanuele and Strebkova, Natalia and Mazerkina, Nadia and Zatelli, Maria Chiara and Lodish, Maya and Horvath, Anelia and de Alexandre, Rodrigo Bertollo and Manning, Allison D and Levy, Isaac and Keil, Margaret F and Sierra, Maria de la Luz and Palmeira, Leonor and Coppieters, Wouter and Georges, Michel and Naves, Luciana A and Jamar, Mauricette and Bours, Vincent and Wu, T John and Choong, Catherine S and Bertherat, Jerome and Chanson, Philippe and Kamenick{\'y}, Peter and Farrell, William E and Barlier, Anne and Quezado, Martha and Bjelobaba, Ivana and Stojilkovic, Stanko S and Wess, Jurgen and Costanzi, Stefano and Liu, Pengfei and Lupski, James R and Beckers, Albert and Stratakis, Constantine A} }