{"doi":"10.64898/2025.12.19.695225","title":"Escape from X inactivation varies across genes and tissues and shapes sex-biased sex chromosome gene expression","abstract":"Abstract Sex differences in human health and disease are shaped by complex interactions between hormones, environment, and genetic factors – including those associated with sex chromosomes. While X chromosome inactivation (XCI) in females generally silences one copy of the X to equalize dosage with males, a subset of genes “escape” XCI and remain expressed from both X chromosomes. In this study, I integrate allele-specific expression data from three females with non-mosaic XCI, sex-biased expression profiles from over 40 tissues, and enhancer activity data from GTEx to explore how variation in the magnitude of XCI escape contributes to sex-biased gene expression across the human body. I confirm that female-biased expression on the X chromosome is a poor proxy for escape from XCI. I find that XCI extends into the pseudoautosomal region (PAR) and that the extent of inactivation strongly predicts male-biased expression of PAR genes. Conversely, stronger escape from XCI in non-PAR X-linked (NPX) genes is associated with more pronounced female-biased expression. Across both PAR and NPX genes, escape patterns are shaped by topologically associating domains (TADs) and sex-biased expression is supported by proximity to sex-biased enhancer activity. These findings reveal a direct, tissue-specific relationship between the strength of XCI escape and the magnitude of sex-biased gene expression, providing a mechanistic framework for understanding how the X chromosome contributes to sex-biased biology.","journal":"bioRxiv (Cold Spring Harbor Laboratory)","year":2025,"id":586852,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":0,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9559,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2025-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":409055,"name":"Alex R. DeCasien","orcid":"0000-0002-6205-5408","position":0,"is_corresponding":true}],"reference_count":42,"raw_metadata":{"citation_network_status":"fetched"},"created_at":"2026-07-19T02:59:32.191237Z","pmid":null,"pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}