Is X-chromosome inactivation randomly?
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X-chromosome inactivation is a process in mammals where one of the two X chromosomes in female cells is randomly inactivated. This mechanism ensures dosage compensation between the sexes. The inactivation is not completely random, as there are variations in the pattern of X chromosome reactivation in different stages of embryonic development and in different cell types. Primed human embryonic stem cells (hESCs) maintain an eroded state of the X chromosome and do not express XIST, while in naïve transition, both XIST and the eroded X chromosome are reactivated . In T cells from patients with systemic lupus erythematosus (SLE), faulty epigenetic control of gene dosage leads to abnormal X-chromosome inactivation, resulting in overexpression of X-linked genes that would normally be transcriptionally silenced . The process of X-chromosome inactivation involves the regulation of non-coding RNA X-inactive specific transcript (XIST) and the recruitment of chromatin complexes that create epigenetic modifications, thereby silencing genes .
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| Papers (5) | Insight |
|---|---|
1 Citations | The paper states that in every cell containing two X chromosomes, one X chromosome is randomly chosen to be inactivated. |
30 Citations | Yes, X-chromosome inactivation is randomly determined during embryonic development, as mentioned in the paper. |
| The paper states that in random X-chromosome inactivation, the probability for the maternal and paternal X chromosomes to become inactivated is equal. Therefore, X-chromosome inactivation is indeed random. | |
| The paper states that the protocols described in the article can be used to determine whether a female has a random or nonrandom pattern of X chromosome inactivation. Therefore, the paper does not directly state whether X-chromosome inactivation is randomly or nonrandomly determined. | |
| The paper does not directly answer the question of whether X-chromosome inactivation is random. The paper focuses on variations in X-chromosome inactivation between primed and naive human embryonic stem cells. |
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