@article {381, title = {Encephalopathy caused by novel mutations in the CMP-sialic acid transporter, SLC35A1.}, journal = {Am J Med Genet A}, volume = {173}, year = {2017}, month = {2017 Nov}, pages = {2906-2911}, abstract = {

Transport of activated nucleotide-sugars into the Golgi is critical for proper glycosylation and mutations in these transporters cause a group of rare genetic disorders termed congenital disorders of glycosylation. We performed exome sequencing on an individual with a profound neurological presentation and identified rare compound heterozygous mutations, p.Thr156Arg and p.Glu196Lys, in the CMP-sialic acid transporter, SLC35A1. Patient primary fibroblasts and serum showed a considerable decrease in the amount of N- and O-glycans terminating in sialic acid. Direct measurement of CMP-sialic acid transport into the Golgi showed a substantial decrease in overall rate of transport. Here we report the identification of the third patient with CMP-sialic acid transporter deficiency, who presented with severe neurological phenotype, but without hematological abnormalities.

}, keywords = {Animals, Brain Diseases, Child, CHO Cells, Cricetinae, Cricetulus, Female, Flow Cytometry, Golgi Apparatus, Humans, Mutation, N-Acetylneuraminic Acid, Nucleotide Transport Proteins, Whole Exome Sequencing}, issn = {1552-4833}, doi = {10.1002/ajmg.a.38412}, author = {Ng, Bobby G and Asteggiano, Carla G and Kircher, Martin and Buckingham, Kati J and Raymond, Kimiyo and Nickerson, Deborah A and Shendure, Jay and Bamshad, Michael J and Ensslen, Matthias and Freeze, Hudson H} } @article {77, title = {ALG1-CDG: Clinical and Molecular Characterization of 39 Unreported Patients.}, journal = {Hum Mutat}, volume = {37}, year = {2016}, month = {2016 07}, pages = {653-60}, abstract = {

Congenital disorders of glycosylation (CDG) arise from pathogenic mutations in over 100 genes leading to impaired protein or lipid glycosylation. ALG1 encodes a β1,4 mannosyltransferase that catalyzes the addition of the first of nine mannose moieties to form a dolichol-lipid linked oligosaccharide intermediate required for proper N-linked glycosylation. ALG1 mutations cause a rare autosomal recessive disorder termed ALG1-CDG. To date 13 mutations in 18 patients from 14 families have been described with varying degrees of clinical severity. We identified and characterized 39 previously unreported cases of ALG1-CDG from 32 families and add 26 new mutations. Pathogenicity of each mutation was confirmed based on its inability to rescue impaired growth or hypoglycosylation of a standard biomarker in an alg1-deficient yeast strain. Using this approach we could not establish a rank order comparison of biomarker glycosylation and patient phenotype, but we identified mutations with a lethal outcome in the first two years of life. The recently identified protein-linked xeno-tetrasaccharide biomarker, NeuAc-Gal-GlcNAc2 , was seen in all 27 patients tested. Our study triples the number of known patients and expands the molecular and clinical correlates of this disorder.

}, keywords = {Biomarkers, Congenital Disorders of Glycosylation, Female, Genes, Lethal, Glycosylation, Humans, Male, Mannosyltransferases, Mutation, Polysaccharides, Sequence Analysis, DNA, Survival Analysis}, issn = {1098-1004}, doi = {10.1002/humu.22983}, author = {Ng, Bobby G and Shiryaev, Sergey A and Rymen, Daisy and Eklund, Erik A and Raymond, Kimiyo and Kircher, Martin and Abdenur, Jose E and Alehan, Fusun and Midro, Alina T and Bamshad, Michael J and Barone, Rita and Berry, Gerard T and Brumbaugh, Jane E and Buckingham, Kati J and Clarkson, Katie and Cole, F Sessions and O{\textquoteright}Connor, Shawn and Cooper, Gregory M and Van Coster, Rudy and Demmer, Laurie A and Diogo, Luisa and Fay, Alexander J and Ficicioglu, Can and Fiumara, Agata and Gahl, William A and Ganetzky, Rebecca and Goel, Himanshu and Harshman, Lyndsay A and He, Miao and Jaeken, Jaak and James, Philip M and Katz, Daniel and Keldermans, Liesbeth and Kibaek, Maria and Kornberg, Andrew J and Lachlan, Katherine and Lam, Christina and Yaplito-Lee, Joy and Nickerson, Deborah A and Peters, Heidi L and Race, Valerie and R{\'e}gal, Luc and Rush, Jeffrey S and Rutledge, S Lane and Shendure, Jay and Souche, Erika and Sparks, Susan E and Trapane, Pamela and Sanchez-Valle, Amarilis and Vilain, Eric and V{\o}llo, Arve and Waechter, Charles J and Wang, Raymond Y and Wolfe, Lynne A and Wong, Derek A and Wood, Tim and Yang, Amy C and Matthijs, Gert and Freeze, Hudson H} } @article {31, title = {SRD5A3-CDG: Expanding the phenotype of a congenital disorder of glycosylation with emphasis on adult onset features.}, journal = {Am J Med Genet A}, volume = {170}, year = {2016}, month = {2016 Dec}, pages = {3165-3171}, abstract = {

Increasing numbers of congenital disorders of glycosylation (CDG) have been reported recently resulting in an expansion of the phenotypes associated with this group of disorders. SRD5A3 codes for polyprenol reductase which converts polyprenol to dolichol. This is a major pathway for dolichol biosynthesis for N-glycosylation, O-mannosylation, C-mannosylation, and GPI anchor synthesis. We present the features of five individuals (three children and two adults) with mutations in SRD5A3 focusing on the variable eye and skin involvement. We compare that to 13 affected individuals from the literature including five adults allowing us to delineate the features that may develop over time with this disorder including kyphosis, retinitis pigmentosa, and cataracts. {\textcopyright} 2016 Wiley Periodicals, Inc.

}, keywords = {3-Oxo-5-alpha-Steroid 4-Dehydrogenase, Adult, Child, Congenital Disorders of Glycosylation, Dolichols, Eye, Female, Glycosylation, Homozygote, Humans, Male, Membrane Proteins, Mutation, Phenotype, Skin, Tretinoin}, issn = {1552-4833}, doi = {10.1002/ajmg.a.37875}, author = {Wheeler, Patricia G and Ng, Bobby G and Sanford, Laura and Sutton, V Reid and Bartholomew, Dennis W and Pastore, Matthew T and Bamshad, Michael J and Kircher, Martin and Buckingham, Kati J and Nickerson, Deborah A and Shendure, Jay and Freeze, Hudson H} } @article {206, title = {Biallelic mutations in BRCA1 cause a new Fanconi anemia subtype.}, journal = {Cancer Discov}, volume = {5}, year = {2015}, month = {2015 Feb}, pages = {135-42}, abstract = {

UNLABELLED: Deficiency in BRCA-dependent DNA interstrand crosslink (ICL) repair is intimately connected to breast cancer susceptibility and to the rare developmental syndrome Fanconi anemia. Bona fide Fanconi anemia proteins, BRCA2 (FANCD1), PALB2 (FANCN), and BRIP1 (FANCJ), interact with BRCA1 during ICL repair. However, the lack of detailed phenotypic and cellular characterization of a patient with biallelic BRCA1 mutations has precluded assignment of BRCA1 as a definitive Fanconi anemia susceptibility gene. Here, we report the presence of biallelic BRCA1 mutations in a woman with multiple congenital anomalies consistent with a Fanconi anemia-like disorder and breast cancer at age 23. Patient cells exhibited deficiency in BRCA1 and RAD51 localization to DNA-damage sites, combined with radial chromosome formation and hypersensitivity to ICL-inducing agents. Restoration of these functions was achieved by ectopic introduction of a BRCA1 transgene. These observations provide evidence in support of BRCA1 as a new Fanconi anemia gene (FANCS).

SIGNIFICANCE: We establish that biallelic BRCA1 mutations cause a distinct FA-S, which has implications for risk counselling in families where both parents harbor BRCA1 mutations. The genetic basis of hereditary cancer susceptibility syndromes provides diagnostic information, insights into treatment strategies, and more accurate recurrence risk counseling to families.

}, keywords = {Adult, Alleles, Base Sequence, BRCA1 Protein, Breast Neoplasms, Fanconi Anemia, Fanconi Anemia Complementation Group Proteins, Female, Genes, BRCA1, Genetic Predisposition to Disease, Humans, Mutation, Young Adult}, issn = {2159-8290}, doi = {10.1158/2159-8290.CD-14-1156}, author = {Sawyer, Sarah L and Tian, Lei and K{\"a}hk{\"o}nen, Marketta and Schwartzentruber, Jeremy and Kircher, Martin and Majewski, Jacek and Dyment, David A and Innes, A Micheil and Boycott, Kym M and Moreau, Lisa A and Moilanen, Jukka S and Greenberg, Roger A} } @article {168, title = {Exome sequencing reveals pathogenic mutations in 91 strains of mice with Mendelian disorders.}, journal = {Genome Res}, volume = {25}, year = {2015}, month = {2015 Jul}, pages = {948-57}, abstract = {

Spontaneously arising mouse mutations have served as the foundation for understanding gene function for more than 100 years. We have used exome sequencing in an effort to identify the causative mutations for 172 distinct, spontaneously arising mouse models of Mendelian disorders, including a broad range of clinically relevant phenotypes. To analyze the resulting data, we developed an analytics pipeline that is optimized for mouse exome data and a variation database that allows for reproducible, user-defined data mining as well as nomination of mutation candidates through knowledge-based integration of sample and variant data. Using these new tools, putative pathogenic mutations were identified for 91 (53\%) of the strains in our study. Despite the increased power offered by potentially unlimited pedigrees and controlled breeding, about half of our exome cases remained unsolved. Using a combination of manual analyses of exome alignments and whole-genome sequencing, we provide evidence that a large fraction of unsolved exome cases have underlying structural mutations. This result directly informs efforts to investigate the similar proportion of apparently Mendelian human phenotypes that are recalcitrant to exome sequencing.

}, keywords = {Animals, Exome, Female, Genetic Diseases, Inborn, Genetic Linkage, Genetic Variation, Genome-Wide Association Study, Genomics, High-Throughput Nucleotide Sequencing, Male, Mice, Mutation, Phenotype, Reproducibility of Results}, issn = {1549-5469}, doi = {10.1101/gr.186882.114}, author = {Fairfield, Heather and Srivastava, Anuj and Ananda, Guruprasad and Liu, Rangjiao and Kircher, Martin and Lakshminarayana, Anuradha and Harris, Belinda S and Karst, Son Yong and Dionne, Louise A and Kane, Coleen C and Curtain, Michelle and Berry, Melissa L and Ward-Bailey, Patricia F and Greenstein, Ian and Byers, Candice and Czechanski, Anne and Sharp, Jocelyn and Palmer, Kristina and Gudis, Polyxeni and Martin, Whitney and Tadenev, Abby and Bogdanik, Laurent and Pratt, C Herbert and Chang, Bo and Schroeder, David G and Cox, Gregory A and Cliften, Paul and Milbrandt, Jeffrey and Murray, Stephen and Burgess, Robert and Bergstrom, David E and Donahue, Leah Rae and Hamamy, Hanan and Masri, Amira and Santoni, Federico A and Makrythanasis, Periklis and Antonarakis, Stylianos E and Shendure, Jay and Reinholdt, Laura G} } @article {134, title = {Expanding the Molecular and Clinical Phenotype of SSR4-CDG.}, journal = {Hum Mutat}, volume = {36}, year = {2015}, month = {2015 Nov}, pages = {1048-51}, abstract = {

Congenital disorders of glycosylation (CDG) are a group of mostly autosomal recessive disorders primarily characterized by neurological abnormalities. Recently, we described a single CDG patient with a de novo mutation in the X-linked gene, Signal Sequence Receptor 4 (SSR4). We performed whole-exome sequencing to identify causal variants in several affected individuals who had either an undifferentiated neurological disorder or unsolved CDG of unknown etiology based on abnormal transferrin glycosylation. We now report eight affected males with either de novo (4) or inherited (4) loss of function mutations in SSR4. Western blot analysis revealed that the mutations caused a complete loss of SSR4 protein. In nearly all cases, the abnormal glycosylation of serum transferrin was only slightly above the accepted normal cutoff range.

}, keywords = {Calcium-Binding Proteins, Congenital Disorders of Glycosylation, DNA Mutational Analysis, Exome, Gene Order, Genes, X-Linked, Genetic Loci, Humans, Male, Membrane Glycoproteins, Mutation, Phenotype, Receptors, Cytoplasmic and Nuclear, Receptors, Peptide}, issn = {1098-1004}, doi = {10.1002/humu.22856}, author = {Ng, Bobby G and Raymond, Kimiyo and Kircher, Martin and Buckingham, Kati J and Wood, Tim and Shendure, Jay and Nickerson, Deborah A and Bamshad, Michael J and Wong, Jonathan T S and Monteiro, Fabiola Paoli and Graham, Brett H and Jackson, Sheryl and Sparkes, Rebecca and Scheuerle, Angela E and Cathey, Sara and Kok, Fernando and Gibson, James B and Freeze, Hudson H} } @article {172, title = {Whole exome sequencing identifies de novo heterozygous CAV1 mutations associated with a novel neonatal onset lipodystrophy syndrome.}, journal = {Am J Med Genet A}, volume = {167A}, year = {2015}, month = {2015 Aug}, pages = {1796-806}, abstract = {

Despite remarkable progress in identifying causal genes for many types of genetic lipodystrophies in the last decade, the molecular basis of many extremely rare lipodystrophy patients with distinctive phenotypes remains unclear. We conducted whole exome sequencing of the parents and probands from six pedigrees with neonatal onset of generalized loss of subcutaneous fat with additional distinctive phenotypic features and report de novo heterozygous null mutations, c.424C>T (p.Q142*) and c.479_480delTT (p.F160*), in CAV1 in a 7-year-old male and a 3-year-old female of European origin, respectively. Both the patients had generalized fat loss, thin mottled skin and progeroid features at birth. The male patient had cataracts requiring extraction at age 30 months and the female patient had pulmonary arterial hypertension. Dermal fibroblasts of the female patient revealed negligible CAV1 immunofluorescence staining compared to control but there were no differences in the number and morphology of caveolae upon electron microscopy examination. Based upon the similarities in the clinical features of these two patients, previous reports of CAV1 mutations in patients with lipodystrophies and pulmonary hypertension, and similar features seen in CAV1 null mice, we conclude that these variants are the most likely cause of one subtype of neonatal onset generalized lipodystrophy syndrome.

}, keywords = {Caveolin 1, Cells, Cultured, Exome, Female, Heterozygote, Humans, Infant, Newborn, Lipodystrophy, Male, Mutation, Pedigree}, issn = {1552-4833}, doi = {10.1002/ajmg.a.37115}, author = {Garg, Abhimanyu and Kircher, Martin and Del Campo, Miguel and Amato, R Stephen and Agarwal, Anil K} } @article {263, title = {Mutations in RSPH1 cause primary ciliary dyskinesia with a unique clinical and ciliary phenotype.}, journal = {Am J Respir Crit Care Med}, volume = {189}, year = {2014}, month = {2014 Mar 15}, pages = {707-17}, abstract = {

RATIONALE: Primary ciliary dyskinesia (PCD) is a genetically heterogeneous recessive disorder of motile cilia, but the genetic cause is not defined for all patients with PCD.

OBJECTIVES: To identify disease-causing mutations in novel genes, we performed exome sequencing, follow-up characterization, mutation scanning, and genotype-phenotype studies in patients with PCD.

METHODS: Whole-exome sequencing was performed using NimbleGen capture and Illumina HiSeq sequencing. Sanger-based sequencing was used for mutation scanning, validation, and segregation analysis.

MEASUREMENTS AND MAIN RESULTS: We performed exome sequencing on an affected sib-pair with normal ultrastructure in more than 85\% of cilia. A homozygous splice-site mutation was detected in RSPH1 in both siblings; parents were carriers. Screening RSPH1 in 413 unrelated probands, including 325 with PCD and 88 with idiopathic bronchiectasis, revealed biallelic loss-of-function mutations in nine additional probands. Five affected siblings of probands in RSPH1 families harbored the familial mutations. The 16 individuals with RSPH1 mutations had some features of PCD; however, nasal nitric oxide levels were higher than in patients with PCD with other gene mutations (98.3 vs. 20.7 nl/min; P < 0.0003). Additionally, individuals with RSPH1 mutations had a lower prevalence (8 of 16) of neonatal respiratory distress, and later onset of daily wet cough than typical for PCD, and better lung function (FEV1), compared with 75 age- and sex-matched PCD cases (73.0 vs. 61.8, FEV1 \% predicted; P = 0.043). Cilia from individuals with RSPH1 mutations had normal beat frequency (6.1 {\textpm} Hz at 25{\textdegree}C), but an abnormal, circular beat pattern.

CONCLUSIONS: The milder clinical disease and higher nasal nitric oxide in individuals with biallelic mutations in RSPH1 provides evidence of a unique genotype-phenotype relationship in PCD, and suggests that mutations in RSPH1 may be associated with residual ciliary function.

}, keywords = {Adolescent, Adult, Child, Cilia, DNA Mutational Analysis, DNA-Binding Proteins, Exome, Female, Genetic Association Studies, Genetic Markers, Genetic Testing, Homozygote, Humans, Kartagener Syndrome, Linear Models, Male, Middle Aged, Mutation, Nasal Mucosa, Sequence Analysis, DNA, Young Adult}, issn = {1535-4970}, doi = {10.1164/rccm.201311-2047OC}, author = {Knowles, Michael R and Ostrowski, Lawrence E and Leigh, Margaret W and Sears, Patrick R and Davis, Stephanie D and Wolf, Whitney E and Hazucha, Milan J and Carson, Johnny L and Olivier, Kenneth N and Sagel, Scott D and Rosenfeld, Margaret and Ferkol, Thomas W and Dell, Sharon D and Milla, Carlos E and Randell, Scott H and Yin, Weining and Sannuti, Aruna and Metjian, Hilda M and Noone, Peadar G and Noone, Peter J and Olson, Christina A and Patrone, Michael V and Dang, Hong and Lee, Hye-Seung and Hurd, Toby W and Gee, Heon Yung and Otto, Edgar A and Halbritter, Jan and Kohl, Stefan and Kircher, Martin and Krischer, Jeffrey and Bamshad, Michael J and Nickerson, Deborah A and Hildebrandt, Friedhelm and Shendure, Jay and Zariwala, Maimoona A} } @article {226, title = {Somatic mutations in cerebral cortical malformations.}, journal = {N Engl J Med}, volume = {371}, year = {2014}, month = {2014 Aug 21}, pages = {733-43}, abstract = {

BACKGROUND: Although there is increasing recognition of the role of somatic mutations in genetic disorders, the prevalence of somatic mutations in neurodevelopmental disease and the optimal techniques to detect somatic mosaicism have not been systematically evaluated.

METHODS: Using a customized panel of known and candidate genes associated with brain malformations, we applied targeted high-coverage sequencing (depth, >=200{\texttimes}) to leukocyte-derived DNA samples from 158 persons with brain malformations, including the double-cortex syndrome (subcortical band heterotopia, 30 persons), polymicrogyria with megalencephaly (20), periventricular nodular heterotopia (61), and pachygyria (47). We validated candidate mutations with the use of Sanger sequencing and, for variants present at unequal read depths, subcloning followed by colony sequencing.

RESULTS: Validated, causal mutations were found in 27 persons (17\%; range, 10 to 30\% for each phenotype). Mutations were somatic in 8 of the 27 (30\%), predominantly in persons with the double-cortex syndrome (in whom we found mutations in DCX and LIS1), persons with periventricular nodular heterotopia (FLNA), and persons with pachygyria (TUBB2B). Of the somatic mutations we detected, 5 (63\%) were undetectable with the use of traditional Sanger sequencing but were validated through subcloning and subsequent sequencing of the subcloned DNA. We found potentially causal mutations in the candidate genes DYNC1H1, KIF5C, and other kinesin genes in persons with pachygyria.

CONCLUSIONS: Targeted sequencing was found to be useful for detecting somatic mutations in patients with brain malformations. High-coverage sequencing panels provide an important complement to whole-exome and whole-genome sequencing in the evaluation of somatic mutations in neuropsychiatric disease. (Funded by the National Institute of Neurological Disorders and Stroke and others.).

}, keywords = {Cerebral Cortex, Classical Lissencephalies and Subcortical Band Heterotopias, DNA Mutational Analysis, Humans, Lissencephaly, Magnetic Resonance Imaging, Malformations of Cortical Development, Mutation, Periventricular Nodular Heterotopia}, issn = {1533-4406}, doi = {10.1056/NEJMoa1314432}, author = {Jamuar, Saumya S and Lam, Anh-Thu N and Kircher, Martin and D{\textquoteright}Gama, Alissa M and Wang, Jian and Barry, Brenda J and Zhang, Xiaochang and Hill, Robert Sean and Partlow, Jennifer N and Rozzo, Aldo and Servattalab, Sarah and Mehta, Bhaven K and Topcu, Meral and Amrom, Dina and Andermann, Eva and Dan, Bernard and Parrini, Elena and Guerrini, Renzo and Scheffer, Ingrid E and Berkovic, Samuel F and Leventer, Richard J and Shen, Yiping and Wu, Bai Lin and Barkovich, A James and Sahin, Mustafa and Chang, Bernard S and Bamshad, Michael and Nickerson, Deborah A and Shendure, Jay and Poduri, Annapurna and Yu, Timothy W and Walsh, Christopher A} } @article {305, title = {Mosaicism of the UDP-galactose transporter SLC35A2 causes a congenital disorder of glycosylation.}, journal = {Am J Hum Genet}, volume = {92}, year = {2013}, month = {2013 Apr 04}, pages = {632-6}, abstract = {

Biochemical analysis and whole-exome sequencing identified mutations in the Golgi-localized UDP-galactose transporter SLC35A2 that define an undiagnosed X-linked congenital disorder of glycosylation (CDG) in three unrelated families. Each mutation reduced UDP-galactose transport, leading to galactose-deficient glycoproteins. Two affected males were somatic mosaics, suggesting that a wild-type SLC35A2 allele may be required for survival. In infancy, the commonly used biomarker transferrin showed abnormal glycosylation, but its appearance became normal later in childhood, without any corresponding clinical improvement. This may indicate selection against cells carrying the mutant allele. To detect other individuals with such mutations, we suggest transferrin testing in infancy. Here, we report somatic mosaicism in CDG, and our work stresses the importance of combining both genetic and biochemical diagnoses.

}, keywords = {Biological Transport, Case-Control Studies, Child, Child, Preschool, Congenital Disorders of Glycosylation, Exome, Female, Glycosylation, Humans, Male, Monosaccharide Transport Proteins, Mosaicism, Mutation, Spectrometry, Mass, Electrospray Ionization, Transferrin, Uridine Diphosphate Galactose}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2013.03.012}, author = {Ng, Bobby G and Buckingham, Kati J and Raymond, Kimiyo and Kircher, Martin and Turner, Emily H and He, Miao and Smith, Joshua D and Eroshkin, Alexey and Szybowska, Marta and Losfeld, Marie E and Chong, Jessica X and Kozenko, Mariya and Li, Chumei and Patterson, Marc C and Gilbert, Rodney D and Nickerson, Deborah A and Shendure, Jay and Bamshad, Michael J and Freeze, Hudson H} }