@article {57, title = {Enrichment of mutations in chromatin regulators in people with Rett syndrome lacking mutations in MECP2.}, journal = {Genet Med}, volume = {19}, year = {2017}, month = {2017 01}, pages = {13-19}, abstract = {

PURPOSE: Rett syndrome (RTT) is a neurodevelopmental disorder caused primarily by de novo mutations in MECP2 and sometimes in CDKL5 and FOXG1. However, some RTT patients lack mutations in these genes.

METHODS: Twenty-two RTT patients without apparent MECP2, CDKL5, and FOXG1 mutations were subjected to both whole-exome sequencing and single-nucleotide polymorphism array-based copy-number variant (CNV) analyses.

RESULTS: Three patients had MECP2 mutations initially missed by clinical testing. Of the remaining 19, 17 (89.5\%) had 29 other likely pathogenic intragenic mutations and/or CNVs (10 patients had 2 or more). Interestingly, 13 patients had mutations in a gene/region previously reported in other neurodevelopmental disorders (NDDs), thereby providing a potential diagnostic yield of 68.4\%. These mutations were significantly enriched in chromatin regulators (corrected P = 0.0068) and moderately enriched in postsynaptic cell membrane molecules (corrected P = 0.076), implicating glutamate receptor signaling.

CONCLUSION: The genetic etiology of RTT without MECP2, CDKL5, and FOXG1 mutations is heterogeneous, overlaps with other NDDs, and complicated by a high mutation burden. Dysregulation of chromatin structure and abnormal excitatory synaptic signaling may form two common pathological bases of RTT.Genet Med 19 1, 13-19.

}, keywords = {Adolescent, Adult, Child, Child, Preschool, Chromatin, DNA Copy Number Variations, Female, Forkhead Transcription Factors, Humans, Infant, Male, Methyl-CpG-Binding Protein 2, Mutation, Nerve Tissue Proteins, Polymorphism, Single Nucleotide, Protein-Serine-Threonine Kinases, Rett Syndrome, Whole Exome Sequencing}, issn = {1530-0366}, doi = {10.1038/gim.2016.42}, author = {Sajan, Samin A and Jhangiani, Shalini N and Muzny, Donna M and Gibbs, Richard A and Lupski, James R and Glaze, Daniel G and Kaufmann, Walter E and Skinner, Steven A and Annese, Fran and Friez, Michael J and Lane, Jane and Percy, Alan K and Neul, Jeffrey L} }