Cathy,

I didn't say all TTs are X-linked; my point was that they are not. A teratogenic environmental exposure would be an epigenetic event and again that was my point. I did not say that we KNOW that folic acid causes TT; I said that we know that the migration of neural crest cells is driven by methylation and given that folate is essential to methylation, it is a strong contender as a factor. New genes associated with TT that were previously unknown have been idenitified in the past two years specfically bc of interest in MTHFR and no doubt others will be found as well. 


Jennifer Tow, IBCLC, USA & France
Intuitive Parenting Network, LLC

Not all tongue-ties are X linked! Some are, but some may be autosomal 
dominant, it depends on the particular gene that causes them. We 
certainly don't know all the genes that contribute to tt, we have only a 
very few identified.

The different gender distribution of anterior and posterior tt's does 
NOT imply an epigenetic cause for posterior ties. It just means the 
specific mechanism of inheritance is different (autosomal versus sex 
linked, for example). Or the cause may be non-genetic entirely, it could 
be developmental (from a teratogenic environmental exposure, for example).

And we don't have a clear link between folate and tt yet. It's an 
interesting hypothesis, but with many 
missing links in the chain of 
theoretical plausibility. I too await further research in all these areas.


Catherine Watson Genna BS, IBCLC  NYC  www.cwgenna.com 


 


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