@article {368, title = {An exome sequencing study of Moebius syndrome including atypical cases reveals an individual with CFEOM3A and a mutation.}, journal = {Cold Spring Harb Mol Case Stud}, volume = {3}, year = {2017}, month = {2017 03}, pages = {a000984}, abstract = {

Moebius syndrome is characterized by congenital unilateral or bilateral facial and abducens nerve palsies (sixth and seventh cranial nerves) causing facial weakness, feeding difficulties, and restricted ocular movements. Abnormalities of the chest wall such as Poland anomaly and variable limb defects are frequently associated with this syndrome. Most cases are isolated; however, rare families with autosomal dominant transmission with incomplete penetrance and variable expressivity have been described. The genetic basis of this condition remains unknown. In a cohort study of nine individuals suspected to have Moebius syndrome (six typical, three atypical), we performed whole-exome sequencing to try to identify a commonly mutated gene. Although no such gene was identified and we did not find mutations in and , we found a de novo heterozygous mutation, p.E410K, in the gene encoding tubulin beta 3 class III (), in an individual with atypical Moebius syndrome. This individual was diagnosed with near-complete ophthalmoplegia, agenesis of the corpus callosum, and absence of the septum pellucidum. No substantial limb abnormalities were noted. Mutations in have been associated with complex cortical dysplasia and other brain malformations and congenital fibrosis of extraocular muscles type 3A (CFEOM3A). Our report highlights the overlap of genetic etiology and clinical differences between CFEOM and Moebius syndrome and describes our approach to identifying candidate genes for typical and atypical Moebius syndrome.

}, keywords = {Child, Child, Preschool, Cohort Studies, Exome, Eye Diseases, Hereditary, Facial Paralysis, Female, Humans, Infant, Male, Malformations of Cortical Development, Mobius Syndrome, Muscular Diseases, Mutation, Ocular Motility Disorders, Ophthalmoplegia, Orbital Diseases, Pedigree, Tubulin, Whole Exome Sequencing}, issn = {2373-2873}, doi = {10.1101/mcs.a000984}, author = {Patel, Ronak M and Liu, David and Gonzaga-Jauregui, Claudia and Jhangiani, Shalini and Lu, James T and Sutton, V Reid and Fernbach, Susan D and Azamian, Mahshid and White, Lisa and Edmond, Jane C and Paysse, Evelyn A and Belmont, John W and Muzny, Donna and Lupski, James R and Gibbs, Richard A and Lewis, Richard Alan and Lee, Brendan H and Lalani, Seema R and Campeau, Philippe M} } @article {135, title = {Exome Sequence Analysis Suggests that Genetic Burden Contributes to Phenotypic Variability and Complex Neuropathy.}, journal = {Cell Rep}, volume = {12}, year = {2015}, month = {2015 Aug 18}, pages = {1169-83}, abstract = {

Charcot-Marie-Tooth (CMT) disease is a clinically and genetically heterogeneous distal symmetric polyneuropathy. Whole-exome sequencing (WES) of 40 individuals from 37 unrelated families with CMT-like peripheral neuropathy refractory to molecular diagnosis identified apparent causal mutations in \~{} 45\% (17/37) of families. Three candidate disease genes are proposed, supported by a combination of genetic and in vivo studies. Aggregate analysis of mutation data revealed a significantly increased number of rare variants across 58 neuropathy-associated genes in subjects versus controls, confirmed in a second ethnically discrete neuropathy cohort, suggesting that mutation burden potentially contributes to phenotypic variability. Neuropathy genes shown to have highly penetrant Mendelizing variants (HPMVs) and implicated by burden in families were shown to interact genetically in a zebrafish assay exacerbating the phenotype established by the suppression of single genes. Our findings suggest that the combinatorial effect of rare variants contributes to disease burden and variable expressivity.

}, keywords = {Animals, Charcot-Marie-Tooth Disease, Exome, Female, Genetic Load, Genetic Variation, HSP40 Heat-Shock Proteins, Humans, Male, Mutation, Myelin P2 Protein, Pedigree, Penetrance, Peripheral Nervous System Diseases, Phenotype, Serine C-Palmitoyltransferase, Suppression, Genetic, Zebrafish}, issn = {2211-1247}, doi = {10.1016/j.celrep.2015.07.023}, author = {Gonzaga-Jauregui, Claudia and Harel, Tamar and Gambin, Tomasz and Kousi, Maria and Griffin, Laurie B and Francescatto, Ludmila and Ozes, Burcak and Karaca, Ender and Jhangiani, Shalini N and Bainbridge, Matthew N and Lawson, Kim S and Pehlivan, Davut and Okamoto, Yuji and Withers, Marjorie and Mancias, Pedro and Slavotinek, Anne and Reitnauer, Pamela J and Goksungur, Meryem T and Shy, Michael and Crawford, Thomas O and Koenig, Michel and Willer, Jason and Flores, Brittany N and Pediaditrakis, Igor and Us, Onder and Wiszniewski, Wojciech and Parman, Yesim and Antonellis, Anthony and Muzny, Donna M and Katsanis, Nicholas and Battaloglu, Esra and Boerwinkle, Eric and Gibbs, Richard A and Lupski, James R} } @article {285, title = {Exonic duplication CNV of NDRG1 associated with autosomal-recessive HMSN-Lom/CMT4D.}, journal = {Genet Med}, volume = {16}, year = {2014}, month = {2014 May}, pages = {386-394}, abstract = {

PURPOSE: Copy-number variations as a mutational mechanism contribute significantly to human disease. Approximately one-half of the patients with Charcot-Marie-Tooth (CMT) disease have a 1.4 Mb duplication copy-number variation as the cause of their neuropathy. However, non-CMT1A neuropathy patients rarely have causative copy-number variations, and to date, autosomal-recessive disease has not been associated with copy-number variation as a mutational mechanism.

METHODS: We performed Agilent 8 {\texttimes} 60 K array comparative genomic hybridization on DNA from 12 recessive Turkish families with CMT disease. Additional molecular studies were conducted to detect breakpoint junctions and to evaluate gene expression levels in a family in which we detected an intragenic duplication copy-number variation.

RESULTS: We detected an ~6.25 kb homozygous intragenic duplication in NDRG1, a gene known to be causative for recessive HMSNL/CMT4D, in three individuals from a Turkish family with CMT neuropathy. Further studies showed that this intragenic copy-number variation resulted in a homozygous duplication of exons 6-8 that caused decreased mRNA expression of NDRG1.

CONCLUSION: Exon-focused high-resolution array comparative genomic hybridization enables the detection of copy-number variation carrier states in recessive genes, particularly small copy-number variations encompassing or disrupting single genes. In families for whom a molecular diagnosis has not been elucidated by conventional clinical assays, an assessment for copy-number variations in known CMT genes might be considered.

}, keywords = {Adult, Base Sequence, Cell Cycle Proteins, Charcot-Marie-Tooth Disease, Comparative Genomic Hybridization, DNA Copy Number Variations, Female, Gene Duplication, Gene Expression, Genes, Recessive, Humans, Intracellular Signaling Peptides and Proteins, Male, Mutation, Refsum Disease, Sequence Analysis, DNA, Turkey, Young Adult}, issn = {1530-0366}, doi = {10.1038/gim.2013.155}, author = {Okamoto, Yuji and Goksungur, Meryem Tuba and Pehlivan, Davut and Beck, Christine R and Gonzaga-Jauregui, Claudia and Muzny, Donna M and Atik, Mehmed M and Carvalho, Claudia M B and Matur, Zeliha and Bayraktar, Serife and Boone, Philip M and Akyuz, Kaya and Gibbs, Richard A and Battaloglu, Esra and Parman, Yesim and Lupski, James R} } @article {298, title = {Exome sequencing resolves apparent incidental findings and reveals further complexity of SH3TC2 variant alleles causing Charcot-Marie-Tooth neuropathy.}, journal = {Genome Med}, volume = {5}, year = {2013}, month = {2013}, pages = {57}, abstract = {

BACKGROUND: The debate regarding the relative merits of whole genome sequencing (WGS) versus exome sequencing (ES) centers around comparative cost, average depth of coverage for each interrogated base, and their relative efficiency in the identification of medically actionable variants from the myriad of variants identified by each approach. Nevertheless, few genomes have been subjected to both WGS and ES, using multiple next generation sequencing platforms. In addition, no personal genome has been so extensively analyzed using DNA derived from peripheral blood as opposed to DNA from transformed cell lines that may either accumulate mutations during propagation or clonally expand mosaic variants during cell transformation and propagation.

METHODS: We investigated a genome that was studied previously by SOLiD chemistry using both ES and WGS, and now perform six independent ES assays (Illumina GAII (x2), Illumina HiSeq (x2), Life Technologies{\textquoteright} Personal Genome Machine (PGM) and Proton), and one additional WGS (Illumina HiSeq).

RESULTS: We compared the variants identified by the different methods and provide insights into the differences among variants identified between ES runs in the same technology platform and among different sequencing technologies. We resolved the true genotypes of medically actionable variants identified in the proband through orthogonal experimental approaches. Furthermore, ES identified an additional SH3TC2 variant (p.M1?) that likely contributes to the phenotype in the proband.

CONCLUSIONS: ES identified additional medically actionable variant calls and helped resolve ambiguous single nucleotide variants (SNV) documenting the power of increased depth of coverage of the captured targeted regions. Comparative analyses of WGS and ES reveal that pseudogenes and segmental duplications may explain some instances of apparent disease mutations in unaffected individuals.

}, issn = {1756-994X}, doi = {10.1186/gm461}, author = {Lupski, James R and Gonzaga-Jauregui, Claudia and Yang, Yaping and Bainbridge, Matthew N and Jhangiani, Shalini and Buhay, Christian J and Kovar, Christie L and Wang, Min and Hawes, Alicia C and Reid, Jeffrey G and Eng, Christine and Muzny, Donna M and Gibbs, Richard A} }