<HashMap><database>GEO</database><file_versions><headers><Content-Type>application/xml</Content-Type></headers><body><files><Other>ftp://ftp.ncbi.nlm.nih.gov/geo/series/GSE303nnn/GSE303977/</Other></files><type>primary</type></body><statusCode>OK</statusCode><statusCodeValue>200</statusCodeValue></file_versions><scores/><additional><omics_type>Transcriptomics</omics_type><species>Homo sapiens</species><gds_type>Expression profiling by high throughput sequencing</gds_type><full_dataset_link>https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE303977</full_dataset_link><repository>GEO</repository><entry_type>GSE</entry_type></additional><is_claimable>false</is_claimable><name>MECP2 Mutations Rewire Human ESC Fate and Bias Cortical Lineage Commitment II</name><description>Rett syndrome arises from loss-of-function mutations in the X-linked chromatin regulator MECP2, yet the earliest molecular derailments in human development remain poorly defined. Using isogenic hESC models carrying three patient-derived MECP2 mutations, we followed the transcriptome from pluripotency through neuro-ectoderm, neural stem, and neural progenitor stages and into four-month cerebral organoids. Stage dominated transcriptional variance, but mutants shared a secondary program enriched for synaptic-membrane and extracellular-matrix genes. Single-cell profiling revealed a naïve-like, hyper-proliferative state marked by up-regulation of ZFP42 at ESC stage. Strikingly, EMX1, a cortical radial-glia determinant, was consistently suppressed from the earliest stage onward, and cerebral organoids subsequently generated fewer excitatory neurons in favour of inhibitory and glial lineages. These data chart a continuous developmental trajectory for MECP2-mutant human cells and nominate ZFP42 and EMX1 dysregulation as tractable entry points for dissecting Rett pathogenesis.</description><dates><publication>2026/04/23</publication></dates><accession>GSE303977</accession><cross_references><GSM>GSM9140078</GSM><GSM>GSM9140079</GSM><GSM>GSM9140077</GSM><GSM>GSM9140081</GSM><GSM>GSM9140082</GSM><GSM>GSM9140083</GSM><GSM>GSM9140084</GSM><GSM>GSM9140080</GSM><GPL>34281</GPL><GSE>303977</GSE><taxon>Homo sapiens</taxon></cross_references></HashMap>