@article {127, title = {Novel genetic causes for cerebral visual impairment.}, journal = {Eur J Hum Genet}, volume = {24}, year = {2016}, month = {2016 May}, pages = {660-5}, abstract = {

Cerebral visual impairment (CVI) is a major cause of low vision in children due to impairment in projection and/or interpretation of the visual input in the brain. Although acquired causes for CVI are well known, genetic causes underlying CVI are largely unidentified. DNAs of 25 patients with CVI and intellectual disability, but without acquired (eg, perinatal) damage, were investigated by whole-exome sequencing. The data were analyzed for de novo, autosomal-recessive, and X-linked variants, and subsequently classified into known, candidate, or unlikely to be associated with CVI. This classification was based on the Online Mendelian Inheritance in Man database, literature reports, variant characteristics, and functional relevance of the gene. After classification, variants in four genes known to be associated with CVI (AHDC1, NGLY1, NR2F1, PGAP1) in 5 patients (20\%) were identified, establishing a conclusive genetic diagnosis for CVI. In addition, in 11 patients (44\%) with CVI, variants in one or more candidate genes were identified (ACP6, AMOT, ARHGEF10L, ATP6V1A, DCAF6, DLG4, GABRB2, GRIN1, GRIN2B, KCNQ3, KCTD19, RERE, SLC1A1, SLC25A16, SLC35A2, SOX5, UFSP2, UHMK1, ZFP30). Our findings show that diverse genetic causes underlie CVI, some of which will provide insight into the biology underlying this disease process.

}, keywords = {Adolescent, Blindness, Cortical, Child, Child, Preschool, Female, Genetic Loci, Humans, Male, Polymorphism, Single Nucleotide, Young Adult}, issn = {1476-5438}, doi = {10.1038/ejhg.2015.186}, author = {Bosch, Dani{\"e}lle G M and Boonstra, F Nienke and de Leeuw, Nicole and Pfundt, Rolph and Nillesen, Willy M and de Ligt, Joep and Gilissen, Christian and Jhangiani, Shalini and Lupski, James R and Cremers, Frans P M and de Vries, Bert B A} } @article {184, title = {Cerebral visual impairment and intellectual disability caused by PGAP1 variants.}, journal = {Eur J Hum Genet}, volume = {23}, year = {2015}, month = {2015 Dec}, pages = {1689-93}, abstract = {

Homozygous variants in PGAP1 (post-GPI attachment to proteins 1) have recently been identified in two families with developmental delay, seizures and/or spasticity. PGAP1 is a member of the glycosylphosphatidylinositol anchor biosynthesis and remodeling pathway and defects in this pathway are a subclass of congenital disorders of glycosylation. Here we performed whole-exome sequencing in an individual with cerebral visual impairment (CVI), intellectual disability (ID), and factor XII deficiency and revealed compound heterozygous variants in PGAP1, c.274_276del (p.(Pro92del)) and c.921_925del (p.(Lys308Asnfs*25)). Subsequently, PGAP1-deficient Chinese hamster ovary (CHO)-cell lines were transfected with either mutant or wild-type constructs and their sensitivity to phosphatidylinositol-specific phospholipase C (PI-PLC) treatment was measured. The mutant constructs could not rescue the PGAP1-deficient CHO cell lines resistance to PI-PLC treatment. In addition, lymphoblastoid cell lines (LCLs) of the affected individual showed no sensitivity to PI-PLC treatment, whereas the LCLs of the heterozygous carrier parents were partially resistant. In conclusion, we report novel PGAP1 variants in a boy with CVI and ID and a proven functional loss of PGAP1 and show, to our knowledge, for the first time this genetic association with CVI.

}, keywords = {Animals, Cell Line, Tumor, Child, CHO Cells, Cricetinae, Cricetulus, Humans, Intellectual Disability, Male, Membrane Proteins, Mutation, Phosphoinositide Phospholipase C, Phosphoric Monoester Hydrolases, Syndrome, Vision Disorders, Visual Perception}, issn = {1476-5438}, doi = {10.1038/ejhg.2015.42}, author = {Bosch, Dani{\"e}lle G M and Boonstra, F Nienke and Kinoshita, Taroh and Jhangiani, Shalini and de Ligt, Joep and Cremers, Frans P M and Lupski, James R and Murakami, Yoshiko and de Vries, Bert B A} } @article {271, title = {NR2F1 mutations cause optic atrophy with intellectual disability.}, journal = {Am J Hum Genet}, volume = {94}, year = {2014}, month = {2014 Feb 06}, pages = {303-9}, abstract = {

Optic nerve atrophy and hypoplasia can be primary disorders or can result from trans-synaptic degeneration arising from cerebral visual impairment (CVI). Here we report six individuals with CVI and/or optic nerve abnormalities, born after an uneventful pregnancy and delivery, who have either de novo heterozygous missense mutations in NR2F1, also known as COUP-TFI, or deletions encompassing NR2F1. All affected individuals show mild to moderate intellectual impairment. NR2F1 encodes a nuclear receptor protein that regulates transcription. A reporter assay showed that missense mutations in the zinc-finger DNA-binding domain and the putative ligand-binding domain decrease NR2F1 transcriptional activity. These findings indicate that NR2F1 plays an important role in the neurodevelopment of the visual system and that its disruption can lead to optic atrophy with intellectual disability.

}, keywords = {Adolescent, Adult, Amino Acid Sequence, Child, Child, Preschool, COUP Transcription Factor I, DNA-Binding Proteins, Female, Genotype, Humans, Intellectual Disability, Male, Molecular Sequence Data, Mutation, Missense, Optic Atrophy, Phenotype, Young Adult, Zinc Fingers}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2014.01.002}, author = {Bosch, Dani{\"e}lle G M and Boonstra, F Nienke and Gonzaga-Jauregui, Claudia and Xu, Mafei and de Ligt, Joep and Jhangiani, Shalini and Wiszniewski, Wojciech and Muzny, Donna M and Yntema, Helger G and Pfundt, Rolph and Vissers, Lisenka E L M and Spruijt, Liesbeth and Blokland, Ellen A W and Chen, Chun-An and Lewis, Richard A and Tsai, Sophia Y and Gibbs, Richard A and Tsai, Ming-Jer and Lupski, James R and Zoghbi, Huda Y and Cremers, Frans P M and de Vries, Bert B A and Schaaf, Christian P} }