Trisomy X is a caused by the presence of an extra X chromosome in females (47,XXX instead of 46,XX). This is also the most common female chromosomal abnormality, occurring in approximately 1 in 1,000 female births.
Other abnormalities of chromosome number include: female tetrasomy X (quadruple X, or 48, XXXX) a rare chromosomal disorder and male Klinefelter syndrome, the presence of an additional X chromosome (47, XXY or XXY).
Some Recent Findings
|* Root length in the permanent teeth of women with an additional X chromosome (47,XXX females) "Increased enamel thickness in the teeth of 47,XXX females is apparently caused by the active enamel gene in all X chromosomes having no increased influence on crown dentin formation. These results in 47,XXX females indicate an increase in root dentin development, at least in the mandible, which together with the data on crown formation reflects a continuous long-lasting effect of the X chromosome on dental development."|
Search Pubmed: Trisomy X
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Cite this page: Hill, M.A. (2019, July 17) Embryology Trisomy X. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Trisomy_X
- © Dr Mark Hill 2019, UNSW Embryology ISBN: 978 0 7334 2609 4 - UNSW CRICOS Provider Code No. 00098G