Chromosome X


The human X chromosome is a submetacentric chromosome that contains ∼5% of the genetic material in the genome. It is characterized by two X–Y homologous (pseudoautosomal) regions that are necessary for normal meiosis. The chromosome is relatively gene‐rich and most of these are subject to X‐inactivation.

Keywords: chromosome X; sequencing; X inactivation; X‐linked diseases, chromosomal abnormalities


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Further Reading

Chelly J (1999) Breakthroughs in molecular and cellular mechanisms underlying X‐linked mental retardation. Human Molecular Genetics 8: 1833–1838.

Ciccodicola A, D'Esposito M, Esposito T, et al. (2000) Differentially regulated and evolved genes in the fully sequenced Xq/Yq pseudoautosomal region. Human Molecular Genetics 9: 395–401.

De Sario A, Geigl E‐M, Palmieri G, D'Urso M and Bernardi G (1996) A compositional map of human chromosome band Xq28. Proceedings of the National Academy of Sciences of the United States of America 93: 1298–1302.

Gianfrancesco F, Sanges R, Esposito T, et al. (2001) Differential divergence of three human pseudoautosomal genes and their mouse homologs: implications for sex chromosome evolution. Genome Research 11: 2095–2100.

Nussbaum RL, McInnes RR and Willard HF (2001) Thompson and Thompson Genetics in Medicine. Philadelphia, PA: WB Saunders.

Strachan T and Read AP (1999) Human Molecular Genetics. New York, NY: John Wiley.

Web Links‐post/Omim/getmap NCBI Online Mendelian Inheritance in Man. OMIM Gene Map Diseases can be listed by chromosome location

Coriell Cell Repositories. Catalog of cytogenetic abnormalities affecting the X chromosome

Collection of cytogenetic abnormalities in cancer. Atlas of Genetics and Cytogenetics in Oncology and Haematology

NCBI Genomes Guide. A site to follow the progress and the state of the art of the Human Genome project

NCBI Online Mendelian Inheritance in Man. Home Page On‐line Mendelian Inheritance in Man, the central database of human genes and Mendelian characters. MIM numbers are the index numbers for entries in OMIM‐bin/nomenclature/

Genew: Human Gene Nomenclature Database Search Engine

NCBI LocusLink

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Franco, Brunella(Jan 2006) Chromosome X. In: eLS. John Wiley & Sons Ltd, Chichester. [doi: 10.1038/npg.els.0005924]