The Lemon Fool

This post is less about Rett's Syndrome specifically and more about how something can be both a genetic mutation, but not hereditary and also be relatively common and present with similar symptoms. Does anyone know the answer to this?

https://www.msn.com/en-gb/health/other/ ... 9#image=17

WickedLester wrote:This post is less about Rett's Syndrome specifically and more about how something can be both a genetic mutation, but not hereditary and also be relatively common and present with similar symptoms. Does anyone know the answer to this?

https://www.msn.com/en-gb/health/other/ ... 9#image=17

The link address says it targets girls... for that to be the case it would be need to caused by spontaneous mutation of a gene on the X-chromosome
- are you sure it cannot be hereditary? as if it can spontaneously appear on a mature X chromosome I would expect it to be possible (but much rarer) on one in a gamete.

Mutations themselves generally result from errors when copying DNA from an old cell to its new replacement, and some parts (hotspots) are more prone to mistakes happening (or are less likely to have mistakes repaired)

WickedLester wrote:This post is less about Rett's Syndrome specifically and more about how something can be both a genetic mutation, but not hereditary and also be relatively common and present with similar symptoms. Does anyone know the answer to this?

https://www.msn.com/en-gb/health/other/ ... 9#image=17

In this day and age, it's easy enough to go to a more specialist resource than MSN - like the International Rett Syndrome Foundation :
https://www.rettsyndrome.org/about-rett ... -syndrome/

In most cases it's a mutation in a gene on the X chromosome, called MECP2 which is involved in the regulation of DNA at a very basic level. I suspect what's going on is that it's so fundamental that any women with it can't make function eggs and so don't have babies, so the main route is new mutations in sperm.

It sounds like one of those things that nobody is quite sure about, but that would be my guess.

WickedLester wrote:This post is less about Rett's Syndrome specifically and more about how something can be both a genetic mutation, but not hereditary and also be relatively common and present with similar symptoms. Does anyone know the answer to this?

https://www.msn.com/en-gb/health/other/ ... 9#image=17

I'm not sure that Rett's Syndrome is exclusive to girls. My daughter suffers from it. There was an argument going around 30 years ago that Rett's syndrome could affect boys but they never came to term as there was a miscarriage. A single faulty chromosome on one of the X's might be more survivable than a faulty X chromosome for an XY boy. Nowadays we understand the fault is on the MeCP2 gene but of which chromosome?

Quite possibly more information than most people want to read:
https://www.frontiersin.org/journals/ge ... 20859/full