Talk:X-inactivation

Barr body

Shouldn't the discovery of the Barr body be mentioned in the history chapter? --Dietzel65 (talk) 20:47, 23 September 2008 (UTC)

Skewing

Should there not be a further mention of skewing on this page? -- 134.36.14.232 (talk) 15:47, 2 October 2008 (UTC) Clarified it here and added a wiki for skewed X-inactivation —Preceding unsigned comment added by TransControl (talk • contribs) 09:14, 12 May 2009 (UTC)

Liane B. Russell

Mention of Russell's work on X inactivation in the mouse (translocations involving Chr 7) ought to be included in this article. —Preceding unsigned comment added by Ebernstine (talk • contribs) 01:09, 9 February 2009 (UTC)

X inactivation

I changed it to this: "The inactive X chromosome is silenced by it being packaged in such a way that it has a transcriptionally inactive structure called heterochromatin." Blueawr (talk) 09:40, 22 August 2012 (UTC)

Does this mean that only the X-active is found in the ova (from a woman)? Or are the ova formed prior X-inactivation, since ova are formed when the woman is still a foetus? 2A00:23C5:C102:9E00:3498:C714:CB93:317F (talk) 16:48, 12 March 2021 (UTC)

Lyon law?

I removed the following from the article. I have never heard of this and the reference does not indicate that it is true. This article is the only source that pops up with a search of the internet.

"The Lyon hypothesis became the Lyon Law on July 22, 2011 at the EMBO 50-years of X-inactivation conference in Oxford." — Preceding unsigned comment added by 199.197.66.5 (talk) 22:13, 8 January 2015 (UTC)

The call for it to be called "Lyon’s law for XCI in XX mammals" is mentioned here. Sminthopsis84 (talk) 16:23, 13 January 2015 (UTC)

References

Activation of embryonic X-chromosomes

This section quotes the cytological work of Takagi et al. (1975), but seems to ignore the 1979 paper by Harper & Monk which showed double dosage of X-chromosome transcription/translation products (HGPRT) when female embryos were compared to males in mice around the 8-cell stage. This concurs with the Okamoto paper quoted "Here, we show that although initially active, the paternal X chromosome undergoes imprinted inactivation from the cleavage stages" (my emphasis), so the process is a bit more complex than stated. I don't have access to the papers behind a paywall, so cant review the actual methodology and have been out of the field for a long time. Semudobia (talk) 12:14, 10 May 2020 (UTC)

"once an X chromosome is inactivated it will remain inactive throughout the lifetime of the cell and its descendants in the organism (its cell line). The result is that"

This is not entirely clear. After all, all the cells in the organism are descendants of the zygote. If X-inactivation occurs in the zygote, and we take the first sentence given here at face value, then all X chromosomes in a female are the same (either the paternal or maternal one). That is not the case. So it needs to be clarified what the zygote and its immediate descendants in the early stages of embryogenesis do with their X chromosomes. I suppose things are still random at that point, and that the inheritance via a cell line kicks in from the pluripotent stem cell stage onwards.

In any case, as stated the text is incoherent and an expert should clarify this. 2A01:CB0C:761:5B00:7CBC:3D81:A448:B226 (talk) 07:24, 13 August 2024 (UTC)