@article {941, title = {MED27 Variants Cause Developmental Delay, Dystonia, and Cerebellar Hypoplasia.}, journal = {Ann Neurol}, volume = {89}, year = {2021}, month = {2021 04}, pages = {828-833}, abstract = {

The Mediator multiprotein complex functions as a regulator of RNA polymerase II-catalyzed gene transcription. In this study, exome sequencing detected biallelic putative disease-causing variants in MED27, encoding Mediator complex subunit 27, in 16 patients from 11 families with a novel neurodevelopmental syndrome. Patient phenotypes are highly homogeneous, including global developmental delay, intellectual disability, axial hypotonia with distal spasticity, dystonic movements, and cerebellar hypoplasia. Seizures and cataracts were noted in severely affected individuals. Identification of multiple patients with biallelic MED27 variants supports the critical role of MED27 in normal human neural development, particularly for the cerebellum. ANN NEUROL 2021;89:828-833.

}, keywords = {Adolescent, Adult, Amino Acid Sequence, Cataract, Cerebellum, Child, Child, Preschool, Developmental Disabilities, Dystonia, Epilepsy, Genetic Variation, Humans, Infant, Mediator Complex, Nervous System Malformations, Phenotype, Whole Exome Sequencing}, issn = {1531-8249}, doi = {10.1002/ana.26019}, author = {Meng, Linyan and Isohanni, Pirjo and Shao, Yunru and GrAHm, Brett H and Hickey, Scott E and Brooks, Stephanie and Suomalainen, Anu and Joset, Pascal and Steindl, Katharina and Rauch, Anita and Hackenberg, Annette and High, Frances A and Armstrong-Javors, Amy and Mencacci, Niccol{\`o} E and Gonz{\`a}lez-Latapi, Paulina and Kamel, Walaa A and Al-Hashel, Jasem Y and Bustos, Bernab{\'e} I and Hernandez, Alejandro V and Krainc, Dimitri and Lubbe, Steven J and Van Esch, Hilde and De Luca, Chiara and Ballon, Katleen and Ravelli, Claudia and Burglen, Lydie and Qebibo, Leila and Calame, Daniel G and Mitani, Tadahiro and Marafi, Dana and Pehlivan, Davut and Saadi, Nebal W and Sahin, Yavuz and Maroofian, Reza and Efthymiou, Stephanie and Houlden, Henry and Maqbool, Shazia and Rahman, Fatima and Gu, Shen and Posey, Jennifer E and Lupski, James R and Hunter, Jill V and Wangler, Michael F and Carroll, Christopher J and Yang, Yaping} } @article {464, title = {Truncating Variants in NAA15 Are Associated with Variable Levels of Intellectual Disability, Autism Spectrum Disorder, and Congenital Anomalies.}, journal = {Am J Hum Genet}, volume = {102}, year = {2018}, month = {2018 05 03}, pages = {985-994}, abstract = {

N-alpha-acetylation is a common co-translational protein modification that is essential for normal cell function in humans. We previously identified the genetic basis of an X-linked infantile lethal Mendelian disorder involving a c.109T>C (p.Ser37Pro) missense variant in NAA10, which encodes the catalytic subunit of the N-terminal acetyltransferase A (NatA) complex. The auxiliary subunit of the NatA complex, NAA15, is the dimeric binding partner for NAA10. Through a genotype-first approach with whole-exome or genome sequencing (WES/WGS) and targeted sequencing analysis, we identified and phenotypically characterized 38 individuals from 33 unrelated families with 25 different de novo or inherited, dominantly acting likely gene disrupting (LGD) variants in NAA15. Clinical features of affected individuals with LGD variants in NAA15 include variable levels of intellectual disability, delayed speech and motor milestones, and autism spectrum disorder. Additionally, mild craniofacial dysmorphology, congenital cardiac anomalies, and seizures are present in some subjects. RNA analysis in cell lines from two individuals showed degradation of the transcripts with LGD variants, probably as a result of nonsense-mediated decay. Functional assays in yeast confirmed a deleterious effect for two of the LGD variants in NAA15. Further supporting a mechanism of haploinsufficiency, individuals with copy-number variant (CNV) deletions involving NAA15 and surrounding genes can present with mild intellectual disability, mild dysmorphic features, motor delays, and decreased growth. We propose that defects in NatA-mediated N-terminal acetylation (NTA) lead to variable levels of neurodevelopmental disorders in humans, supporting the importance of the NatA complex in normal human development.

}, keywords = {Abnormalities, Multiple, Adolescent, Adult, Autism Spectrum Disorder, Cell Line, Child, Exons, Female, Gene Expression Regulation, Genetic Predisposition to Disease, Genetic Variation, Humans, Intellectual Disability, Male, Middle Aged, Mutation, N-Terminal Acetyltransferase A, N-Terminal Acetyltransferase E, Pedigree, Phenotype, RNA, Messenger, Saccharomyces cerevisiae}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2018.03.004}, author = {Cheng, Hanyin and Dharmadhikari, Avinash V and Varland, Sylvia and Ma, Ning and Domingo, Deepti and Kleyner, Robert and Rope, Alan F and Yoon, Margaret and Stray-Pedersen, Asbj{\o}rg and Posey, Jennifer E and Crews, Sarah R and Eldomery, Mohammad K and Akdemir, Zeynep Coban and Lewis, Andrea M and Sutton, Vernon R and Rosenfeld, Jill A and Conboy, Erin and Agre, Katherine and Xia, Fan and Walkiewicz, Magdalena and Longoni, Mauro and High, Frances A and van Slegtenhorst, Marjon A and Mancini, Grazia M S and Finnila, Candice R and van Haeringen, Arie and den Hollander, Nicolette and Ruivenkamp, Claudia and Naidu, Sakkubai and Mahida, Sonal and Palmer, Elizabeth E and Murray, Lucinda and Lim, Derek and Jayakar, Parul and Parker, Michael J and Giusto, Stefania and Stracuzzi, Emanuela and Romano, Corrado and Beighley, Jennifer S and Bernier, Raphael A and K{\"u}ry, S{\'e}bastien and Nizon, Mathilde and Corbett, Mark A and Shaw, Marie and Gardner, Alison and Barnett, Christopher and Armstrong, Ruth and Kassahn, Karin S and Van Dijck, Anke and Vandeweyer, Geert and Kleefstra, Tjitske and Schieving, Jolanda and Jongmans, Marjolijn J and de Vries, Bert B A and Pfundt, Rolph and Kerr, Bronwyn and Rojas, Samantha K and Boycott, Kym M and Person, Richard and Willaert, Rebecca and Eichler, Evan E and Kooy, R Frank and Yang, Yaping and Wu, Joseph C and Lupski, James R and Arnesen, Thomas and Cooper, Gregory M and Chung, Wendy K and Gecz, Jozef and Stessman, Holly A F and Meng, Linyan and Lyon, Gholson J} } @article {334, title = {A Recurrent De Novo Variant in NACC1 Causes a Syndrome Characterized by Infantile Epilepsy, Cataracts, and Profound Developmental Delay.}, journal = {Am J Hum Genet}, volume = {100}, year = {2017}, month = {2017 Feb 02}, pages = {343-351}, abstract = {

Whole-exome sequencing (WES) has increasingly enabled new pathogenic gene variant identification for undiagnosed neurodevelopmental disorders and provided insights into both gene function and disease biology. Here, we describe seven children with a neurodevelopmental disorder characterized by microcephaly, profound developmental delays and/or intellectual disability, cataracts, severe epilepsy including infantile spasms, irritability, failure to thrive, and stereotypic hand movements. Brain imaging in these individuals reveals delay in myelination and cerebral atrophy. We observe an identical recurrent de novo heterozygous c.892C>T (p.Arg298Trp) variant in the nucleus accumbens associated 1 (NACC1) gene in seven affected individuals. One of the seven individuals is mosaic for this variant. NACC1 encodes a transcriptional repressor implicated in gene expression and has not previously been associated with germline disorders. The probability of finding the same missense NACC1 variant by chance in 7 out of 17,228 individuals who~underwent WES for diagnoses of neurodevelopmental phenotypes is extremely small and achieves genome-wide significance (p~= 1.25~{\texttimes} 10). Selective constraint against missense variants in NACC1 makes this excess of an identical missense variant in all seven individuals more remarkable. Our findings are consistent with a germline recurrent mutational hotspot associated with an allele-specific neurodevelopmental phenotype in NACC1.

}, keywords = {Alleles, Amino Acid Sequence, Brain, Cataract, Child, Child, Preschool, Female, Genetic Variation, Genome-Wide Association Study, Humans, Infant, Intellectual Disability, Magnetic Resonance Imaging, Male, Microcephaly, Mutation, Missense, Neoplasm Proteins, Pedigree, Phenotype, Repressor Proteins, Spasms, Infantile}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2016.12.013}, author = {Schoch, Kelly and Meng, Linyan and Szelinger, Szabolcs and Bearden, David R and Stray-Pedersen, Asbjorg and Busk, Oyvind L and Stong, Nicholas and Liston, Eriskay and Cohn, Ronald D and Scaglia, Fernando and Rosenfeld, Jill A and Tarpinian, Jennifer and Skraban, Cara M and Deardorff, Matthew A and Friedman, Jeremy N and Akdemir, Zeynep Coban and Walley, Nicole and Mikati, Mohamad A and Kranz, Peter G and Jasien, Joan and McConkie-Rosell, Allyn and McDonald, Marie and Wechsler, Stephanie Burns and Freemark, Michael and Kansagra, Sujay and Freedman, Sharon and Bali, Deeksha and Millan, Francisca and Bale, Sherri and Nelson, Stanley F and Lee, Hane and Dorrani, Naghmeh and Goldstein, David B and Xiao, Rui and Yang, Yaping and Posey, Jennifer E and Martinez-Agosto, Julian A and Lupski, James R and Wangler, Michael F and Shashi, Vandana} }