@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 {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} }