Are birthmarks hereditary?

Babies are often born with blemishes and there are a variety of causes for these marks. 

7th September 2017
Are birthmarks hereditary? (Getty)

Asked by: Alister Kennedy, Ayrshire

Almost all newborn children have some sort of birthmark. They are not hereditary but in some cases can be related to specific conditions caused by a gene mutation (though not a mutation passed on from a parent). In general, they appear because of abnormal blood vessels, or the nerves controlling the widening or narrowing of the blood vessels; or else because of clusters of overgrown pigmented cells. 


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