3 doctors weighed in:
Why do some people have birth marks?
3 doctors weighed in

Dr. M. Christine Lee
Dermatology
1 doctor agrees
In brief: No one really knows
Nobody really knows what causes birthmarks.
Vascular birthmarks are not hereditary but thought to be caused by overdevelopment or overgrowth of blood vessels. Many theories for different types of birthmarks: some may be hereditary (most are not), some caused by random genetic mutations, overgrowth of pigmented cells called melanocytes, abnormal collection or overgrowth of blood vessels.

In brief: No one really knows
Nobody really knows what causes birthmarks.
Vascular birthmarks are not hereditary but thought to be caused by overdevelopment or overgrowth of blood vessels. Many theories for different types of birthmarks: some may be hereditary (most are not), some caused by random genetic mutations, overgrowth of pigmented cells called melanocytes, abnormal collection or overgrowth of blood vessels.
Dr. M. Christine Lee
Dr. M. Christine Lee
Thank
Dr. Thomas Fiala
Surgery - Plastics
In brief: Random luck
In most cases. Occasionally, there are birthmarks that are associated with genetic syndromes, but these are less common.

In brief: Random luck
In most cases. Occasionally, there are birthmarks that are associated with genetic syndromes, but these are less common.
Dr. Thomas Fiala
Dr. Thomas Fiala
Thank
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