@article {914, title = {Exome sequencing implicates genetic disruption of prenatal neuro-gliogenesis in sporadic congenital hydrocephalus.}, journal = {Nat Med}, volume = {26}, year = {2020}, month = {2020 11}, pages = {1754-1765}, abstract = {

Congenital hydrocephalus (CH), characterized by enlarged brain ventricles, is considered a disease of excessive cerebrospinal fluid (CSF) accumulation and thereby treated with neurosurgical CSF diversion with high morbidity and failure rates. The poor neurodevelopmental outcomes and persistence of ventriculomegaly in some post-surgical patients highlight our limited knowledge of disease mechanisms. Through whole-exome sequencing of 381 patients (232 trios) with sporadic, neurosurgically treated CH, we found that damaging de novo mutations account for >17\% of cases, with five different genes exhibiting a significant de novo mutation burden. In all, rare, damaging mutations with large effect contributed to ~22\% of sporadic CH cases. Multiple CH genes are key regulators of neural stem cell biology and converge in human transcriptional networks and cell types pertinent for fetal neuro-gliogenesis. These data implicate genetic disruption of early brain development, not impaired CSF dynamics, as the primary pathomechanism of a significant number of patients with sporadic CH.

}, keywords = {Brain, Cerebral Ventricles, Exome, Female, Genetic Predisposition to Disease, Humans, Hydrocephalus, Male, Mutation, Neural Stem Cells, Neurogenesis, Neuroglia, Transcription Factors, Tripartite Motif Proteins, Ubiquitin-Protein Ligases, Whole Exome Sequencing}, issn = {1546-170X}, doi = {10.1038/s41591-020-1090-2}, author = {Jin, Sheng Chih and Dong, Weilai and Kundishora, Adam J and Panchagnula, Shreyas and Moreno-De-Luca, Andres and Furey, Charuta G and Allocco, August A and Walker, Rebecca L and Nelson-Williams, Carol and Smith, Hannah and Dunbar, Ashley and Conine, Sierra and Lu, Qiongshi and Zeng, Xue and Sierant, Michael C and Knight, James R and Sullivan, William and Duy, Phan Q and DeSpenza, Tyrone and Reeves, Benjamin C and Karimy, Jason K and Marlier, Arnaud and Castaldi, Christopher and Tikhonova, Irina R and Li, Boyang and Pe{\~n}a, Helena Perez and Broach, James R and Kabachelor, Edith M and Ssenyonga, Peter and Hehnly, Christine and Ge, Li and Keren, Boris and Timberlake, Andrew T and Goto, June and Mangano, Francesco T and Johnston, James M and Butler, William E and Warf, Benjamin C and Smith, Edward R and Schiff, Steven J and Limbrick, David D and Heuer, Gregory and Jackson, Eric M and Iskandar, Bermans J and Mane, Shrikant and Haider, Shozeb and Guclu, Bulent and Bayri, Yasar and Sahin, Yener and Duncan, Charles C and Apuzzo, Michael L J and DiLuna, Michael L and Hoffman, Ellen J and {\v S}estan, Nenad and Ment, Laura R and Alper, Seth L and Bilguvar, Kaya and Geschwind, Daniel H and G{\"u}nel, Murat and Lifton, Richard P and Kahle, Kristopher T} } @article {208, title = {Brain malformations associated with Knobloch syndrome--review of literature, expanding clinical spectrum, and identification of novel mutations.}, journal = {Pediatr Neurol}, volume = {51}, year = {2014}, month = {2014 Dec}, pages = {806-813.e8}, abstract = {

BACKGROUND: Knobloch syndrome is a rare, autosomal recessive, developmental disorder characterized by stereotyped ocular abnormalities with or without occipital skull deformities (encephalocele, bone defects, and cutis aplasia). Although there is clear heterogeneity in clinical presentation, central nervous system malformations, aside from the characteristic encephalocele, have not typically been considered a component of the disease phenotype.

METHODS: Four patients originally presented for genetic evaluation of symptomatic structural brain malformations. Whole-genome genotyping, whole-exome sequencing, and confirmatory Sanger sequencing were performed. Using immunohistochemical analysis, we investigated the protein expression pattern of COL18A1 in the mid-fetal and adult human cerebral cortex and then analyzed the spatial and temporal changes in the expression pattern of COL18A1 during human cortical development using the Human Brain Transcriptome database.

RESULTS: We identified two novel homozygous deleterious frame-shift mutations in the COL18A1 gene. On further investigation of these patients and their families, we found that many exhibited certain characteristics of Knobloch syndrome, including pronounced ocular defects. Our data strongly support an important role for COL18A1 in brain development, and this report contributes to an enhanced characterization of the brain malformations that can result from deficiencies of collagen XVIII.

CONCLUSIONS: This case series highlights the diagnostic power and clinical utility of whole-exome sequencing technology-allowing clinicians and physician scientists to better understand the pathophysiology and presentations of rare diseases. We suggest that patients who are clinically diagnosed with Knobloch syndrome and/or found to have COL18A1 mutations via genetic screening should be investigated for potential structural brain abnormalities even in the absence of an encephalocele.

}, keywords = {Adolescent, Adult, Cerebral Cortex, Collagen Type XVIII, Consanguinity, Encephalocele, Exome, Female, Fetus, Humans, Male, Mutation, Retinal Degeneration, Retinal Detachment, Young Adult}, issn = {1873-5150}, doi = {10.1016/j.pediatrneurol.2014.08.025}, author = {{\c C}a{\u g}layan, Ahmet Okay and Baranoski, Jacob F and Aktar, Fesih and Han, Wengi and Tuysuz, Beyhan and Guzel, Aslan and Guclu, Bulent and Kaymak{\c c}alan, Hande and Aktekin, Berrin and Akg{\"u}m{\"u}{\c s}, G{\"o}zde Tu{\u g}ce and Murray, Phillip B and Erson-Omay, Emine Z and Caglar, Caner and Bakircioglu, Mehmet and Sakalar, Yildirim Bayezit and Guzel, Ebru and Demir, Nihat and Tuncer, Oguz and Senturk, Senem and Ekici, Bar{\i}{\c s} and Minja, Frank J and {\v S}estan, Nenad and Yasuno, Katsuhito and Bilguvar, Kaya and Caksen, Huseyin and G{\"u}nel, Murat} }