@article {780,
	title = {De novo EIF2AK1 and EIF2AK2 Variants Are Associated with Developmental Delay, Leukoencephalopathy, and Neurologic Decompensation.},
	journal = {Am J Hum Genet},
	volume = {106},
	year = {2020},
	month = {2020 04 02},
	pages = {570-583},
	abstract = {<p>EIF2AK1 and EIF2AK2 encode members of the eukaryotic translation initiation factor 2 alpha kinase (EIF2AK) family that inhibits protein synthesis in response to physiologic stress conditions. EIF2AK2 is also involved in innate immune response and the regulation of signal transduction, apoptosis, cell proliferation, and differentiation. Despite these findings, human disorders associated with deleterious variants in EIF2AK1 and EIF2AK2 have not been reported. Here, we describe the identification of nine unrelated individuals with heterozygous de novo missense variants in EIF2AK1 (1/9) or EIF2AK2 (8/9). Features seen in these nine individuals include white matter alterations (9/9), developmental delay (9/9), impaired language (9/9), cognitive impairment (8/9), ataxia (6/9), dysarthria in probands with verbal ability (6/9), hypotonia (7/9), hypertonia (6/9), and involuntary movements (3/9). Individuals with EIF2AK2 variants also exhibit neurological regression in the setting of febrile illness or infection. We use mammalian cell lines and proband-derived fibroblasts to further confirm the pathogenicity of variants in these genes and found reduced kinase activity. EIF2AKs phosphorylate eukaryotic translation initiation factor 2 subunit 1 (EIF2S1, also known as EIF2α), which then inhibits EIF2B activity. Deleterious variants in genes encoding EIF2B proteins cause childhood ataxia with central nervous system hypomyelination/vanishing white matter (CACH/VWM), a leukodystrophy characterized by neurologic regression in the setting of febrile illness and other stressors. Our findings indicate that EIF2AK2 missense variants cause a neurodevelopmental syndrome that may share phenotypic and pathogenic mechanisms with CACH/VWM.</p>},
	keywords = {Adolescent, Ataxia, Child, Child, Preschool, Developmental Disabilities, eIF-2 Kinase, Female, Genetic Variation, Hereditary Central Nervous System Demyelinating Diseases, Humans, Infant, Leukoencephalopathies, Male, Nervous System Malformations, White Matter},
	issn = {1537-6605},
	doi = {10.1016/j.ajhg.2020.02.016},
	author = {Mao, Dongxue and Reuter, Chloe M and Ruzhnikov, Maura R Z and Beck, Anita E and Farrow, Emily G and Emrick, Lisa T and Rosenfeld, Jill A and Mackenzie, Katherine M and Robak, Laurie and Wheeler, Matthew T and Burrage, Lindsay C and Jain, Mahim and Liu, Pengfei and Calame, Daniel and K{\"u}ry, S{\'e}bastien and Sillesen, Martin and Schmitz-Abe, Klaus and Tonduti, Davide and Spaccini, Luigina and Iascone, Maria and Genetti, Casie A and Koenig, Mary K and Graf, Madeline and Tran, Alyssa and Alejandro, Mercedes and Lee, Brendan H and Thiffault, Isabelle and Agrawal, Pankaj B and Bernstein, Jonathan A and Bellen, Hugo J and Chao, Hsiao-Tuan}
}
@article {709,
	title = {Clinical Spectrum and Functional Consequences Associated with Bi-Allelic Pathogenic  Variants.},
	journal = {J Clin Med},
	volume = {8},
	year = {2019},
	month = {2019 Nov 19},
	abstract = {<p> (PNPase-polynucleotide phosphorylase) is involved in multiple RNA processing functions in the mitochondria. Bi-allelic pathogenic  variants cause heterogeneous clinical phenotypes affecting multiple organs without any established genotype-phenotype correlations. Defects in PNPase can cause variable combined respiratory chain complex defects. Recently, it has been suggested that PNPase can lead to activation of an innate immune response. To better understand the clinical and molecular spectrum of patients with bi-allelic  variants, we captured detailed clinical and molecular phenotypes of all 17 patients reported in the literature, plus seven new patients, including a 78-year-old male with the longest reported survival. A functional follow-up of genomic sequencing by cDNA studies confirmed a splicing defect in a novel, apparently synonymous, variant. Patient fibroblasts showed an accumulation of mitochondrial unprocessed  transcripts, while blood showed an increased interferon response. Our findings suggest that functional analyses of the RNA processing function of PNPase are more sensitive than testing downstream defects in oxidative phosphorylation (OXPHPOS) enzyme activities. This research extends our knowledge of the clinical and functional consequences of bi-allelic pathogenic  variants that may guide management and further efforts into understanding the pathophysiological mechanisms for therapeutic development.</p>},
	issn = {2077-0383},
	doi = {10.3390/jcm8112020},
	author = {Rius, Rocio and Van Bergen, Nicole J and Compton, Alison G and Riley, Lisa G and Kava, Maina P and Balasubramaniam, Shanti and Amor, David J and Fanjul-Fernandez, Miriam and Cowley, Mark J and Fahey, Michael C and Koenig, Mary K and Enns, Gregory M and Sadedin, Simon and Wilson, Meredith J and Tan, Tiong Y and Thorburn, David R and Christodoulou, John}
}
@article {673,
	title = {Reanalysis of Clinical Exome Sequencing Data.},
	journal = {N Engl J Med},
	volume = {380},
	year = {2019},
	month = {2019 06 20},
	pages = {2478-2480},
	keywords = {Exome, Genetic Diseases, Inborn, Genetic Testing, Humans, Mutation, Phenotype, Sequence Analysis, DNA, Whole Exome Sequencing},
	issn = {1533-4406},
	doi = {10.1056/NEJMc1812033},
	author = {Liu, Pengfei and Meng, Linyan and Normand, Elizabeth A and Xia, Fan and Song, Xiaofei and Ghazi, Andrew and Rosenfeld, Jill and Magoulas, Pilar L and Braxton, Alicia and Ward, Patricia and Dai, Hongzheng and Yuan, Bo and Bi, Weimin and Xiao, Rui and Wang, Xia and Chiang, Theodore and Vetrini, Francesco and He, Weimin and Cheng, Hanyin and Dong, Jie and Gijavanekar, Charul and Benke, Paul J and Bernstein, Jonathan A and Eble, Tanya and Eroglu, Yasemen and Erwin, Deanna and Escobar, Luis and Gibson, James B and Gripp, Karen and Kleppe, Soledad and Koenig, Mary K and Lewis, Andrea M and Natowicz, Marvin and Mancias, Pedro and Minor, LaKeesha and Scaglia, Fernando and Schaaf, Christian P and Streff, Haley and Vernon, Hilary and Uhles, Crescenda L and Zackai, Elaine H and Wu, Nan and Sutton, V Reid and Beaudet, Arthur L and Muzny, Donna and Gibbs, Richard A and Posey, Jennifer E and Lalani, Seema and Shaw, Chad and Eng, Christine M and Lupski, James R and Yang, Yaping}
}
