@article {999, title = {DLG4-related synaptopathy: a new rare brain disorder.}, journal = {Genet Med}, volume = {23}, year = {2021}, month = {2021 05}, pages = {888-899}, abstract = {

PURPOSE: Postsynaptic density protein-95 (PSD-95), encoded by DLG4, regulates excitatory synaptic function in the brain. Here we present the clinical and genetic features of 53 patients (42 previously unpublished) with DLG4 variants.

METHODS: The clinical and genetic information were~collected through GeneMatcher collaboration. All the individuals were investigated by local clinicians and the gene variants were identified by clinical exome/genome sequencing.

RESULTS: The clinical picture was predominated by early onset global developmental delay, intellectual disability, autism spectrum disorder, and attention deficit-hyperactivity disorder, all of which point to a brain disorder. Marfanoid habitus, which was previously suggested to be a characteristic feature of DLG4-related phenotypes, was found in only nine individuals and despite some overlapping features, a distinct facial dysmorphism could not~be established. Of the 45 different DLG4 variants, 39 were predicted to lead to loss of protein function and the majority occurred de novo (four with unknown origin). The six missense variants identified were suggested to lead to structural or functional changes by protein modeling studies.

CONCLUSION: The present study shows that clinical manifestations associated with DLG4 overlap with those found in other neurodevelopmental disorders of synaptic dysfunction; thus, we designate this group of disorders as DLG4-related synaptopathy.

}, keywords = {Autism Spectrum Disorder, Brain, Brain Diseases, Disks Large Homolog 4 Protein, Humans, Intellectual Disability, Neurodevelopmental Disorders, Phenotype}, issn = {1530-0366}, doi = {10.1038/s41436-020-01075-9}, author = {Rodr{\'\i}guez-Palmero, Agust{\'\i} and Boerrigter, Melissa Maria and G{\'o}mez-Andr{\'e}s, David and Aldinger, Kimberly A and Marcos-Alcalde, {\'I}{\~n}igo and Popp, Bernt and Everman, David B and Lovgren, Alysia Kern and Arpin, Stephanie and Bahrambeigi, Vahid and Beunders, Gea and Bisgaard, Anne-Marie and Bjerregaard, V A and Bruel, Ange-Line and Challman, Thomas D and Cogn{\'e}, Benjamin and Coubes, Christine and de Man, Stella A and Denomm{\'e}-Pichon, Anne-Sophie and Dye, Thomas J and Elmslie, Frances and Feuk, Lars and Garcia-Minaur, Sixto and Gertler, Tracy and Giorgio, Elisa and Gruchy, Nicolas and Haack, Tobias B and Haldeman-Englert, Chad R and Haukanes, Bj{\o}rn Ivar and Hoyer, Juliane and Hurst, Anna C E and Isidor, Bertrand and Soller, Maria Johansson and Kushary, Sulagna and Kvarnung, Malin and Landau, Yuval E and Leppig, Kathleen A and Lindstrand, Anna and Kleinendorst, Lotte and MacKenzie, Alex and Mandrile, Giorgia and Mendelsohn, Bryce A and Moghadasi, Setareh and Morton, Jenny E and Moutton, S{\'e}bastien and M{\"u}ller, Amelie J and O{\textquoteright}Leary, Melanie and Pacio-Miguez, Marta and Palomares-Bralo, Maria and Parikh, Sumit and Pfundt, Rolph and Pode-Shakked, Ben and Rauch, Anita and Repnikova, Elena and Revah-Politi, Anya and Ross, Meredith J and Ruivenkamp, Claudia A L and Sarrazin, Elisabeth and Savatt, Juliann M and Schluter, Agatha and Sch{\"o}newolf-Greulich, Bitten and Shad, Zohra and Shaw-Smith, Charles and Shieh, Joseph T and Shohat, Motti and Spranger, Stephanie and Thiese, Heidi and Mau-Them, Frederic Tran and van Bon, Bregje and van de Burgt, Ineke and van de Laar, Ingrid M B H and van Drie, Esm{\'e}e and van Haelst, Mieke M and van Ravenswaaij-Arts, Conny M and Verdura, Edgard and Vitobello, Antonio and Waldm{\"u}ller, Stephan and Whiting, Sharon and Zweier, Christiane and Prada, Carlos E and de Vries, Bert B A and Dobyns, William B and Reiter, Simone F and G{\'o}mez-Puertas, Paulino and Pujol, Aurora and T{\"u}mer, Zeynep} } @article {1022, title = {POLRMT mutations impair mitochondrial transcription causing neurological disease.}, journal = {Nat Commun}, volume = {12}, year = {2021}, month = {2021 02 18}, pages = {1135}, abstract = {

While >300 disease-causing variants have been identified in the mitochondrial DNA (mtDNA) polymerase γ, no mitochondrial phenotypes have been associated with POLRMT, the RNA polymerase responsible for transcription of the mitochondrial genome. Here, we characterise the clinical and molecular nature of POLRMT variants in eight individuals from seven unrelated families. Patients present with global developmental delay, hypotonia, short stature, and speech/intellectual disability in childhood; one subject displayed an indolent progressive external ophthalmoplegia phenotype. Massive parallel sequencing of all subjects identifies recessive and dominant variants in the POLRMT gene. Patient fibroblasts have a defect in mitochondrial mRNA synthesis, but no mtDNA deletions or copy number abnormalities. The in vitro characterisation of the recombinant POLRMT mutants reveals variable, but deleterious effects on mitochondrial transcription. Together, our in vivo and in vitro functional studies of POLRMT variants establish defective mitochondrial transcription as an important disease mechanism.

}, keywords = {Adolescent, Adult, Child, DNA, Mitochondrial, DNA-Directed RNA Polymerases, Female, Fibroblasts, Humans, Infant, Male, Mitochondria, Mutation, Nervous System Diseases, Oxidative Phosphorylation, Pedigree, Protein Domains, Protein Subunits, RNA, Messenger, Transcription, Genetic, Young Adult}, issn = {2041-1723}, doi = {10.1038/s41467-021-21279-0}, author = {Ol{\'a}hov{\'a}, Monika and Peter, Bradley and Szilagyi, Zsolt and Diaz-Maldonado, Hector and Singh, Meenakshi and Sommerville, Ewen W and Blakely, Emma L and Collier, Jack J and Hoberg, Emily and Str{\'a}neck{\'y}, Viktor and Hartmannov{\'a}, Hana and Bleyer, Anthony J and McBride, Kim L and Bowden, Sasigarn A and Korandov{\'a}, Zuzana and Pecinov{\'a}, Alena and Ropers, Hans-Hilger and Kahrizi, Kimia and Najmabadi, Hossein and Tarnopolsky, Mark A and Brady, Lauren I and Weaver, K Nicole and Prada, Carlos E and {\~O}unap, Katrin and Wojcik, Monica H and Pajusalu, Sander and Syeda, Safoora B and Pais, Lynn and Estrella, Elicia A and Bruels, Christine C and Kunkel, Louis M and Kang, Peter B and Bonnen, Penelope E and Mr{\'a}{\v c}ek, Tom{\'a}{\v s} and Kmoch, Stanislav and Gorman, Gr{\'a}inne S and Falkenberg, Maria and Gustafsson, Claes M and Taylor, Robert W} } @article {251, title = {Clinical utility of whole-exome sequencing in rare diseases: Galactosialidosis.}, journal = {Eur J Med Genet}, volume = {57}, year = {2014}, month = {2014 Jul}, pages = {339-344}, abstract = {

Rare genetic disorders can go undiagnosed for years as the entire spectrum of phenotypic variation is not well characterized given the reduced number of patients reported in the literature and the low frequency at which these occur. Moreover, the current paradigm for clinical diagnostics defines disease diagnosis by a specified spectrum of phenotypic findings; when such parameters are either missing, or other findings not usually observed are seen, the phenotype driven approach to diagnosis may result in a specific etiological diagnosis not even being considered within the differential diagnosis. The novel implementation of genomic sequencing approaches to investigate rare genetic disorders is allowing not only the discovery of new genes, but also the phenotypic expansion of known Mendelian genetic disorders. Here we report the detailed clinical assessment of a patient with a rare genetic disorder with undefined molecular diagnosis. We applied whole-exome sequencing to this patient and unaffected parents in order to identify the molecular cause of her disorder. We identified compound heterozygous mutations in the CTSA gene, responsible for causing galactosialidosis; the molecular diagnosis was further confirmed by biochemical studies. This report expands on the clinical spectrum of this rare lysosomal disorder and exemplifies how genomic approaches are further elucidating the characterization and understanding of genetic diseases.

}, keywords = {Adult, Cathepsin A, Exome, Female, Humans, Lysosomal Storage Diseases, Mutation, Rare Diseases, Sequence Analysis, DNA, Young Adult}, issn = {1878-0849}, doi = {10.1016/j.ejmg.2014.04.005}, author = {Prada, Carlos E and Gonzaga-Jauregui, Claudia and Tannenbaum, Rebecca and Penney, Samantha and Lupski, James R and Hopkin, Robert J and Sutton, V Reid} }