# Mongolian spot common on mixed race children?

**URL:** <https://boards.straightdope.com/t/mongolian-spot-common-on-mixed-race-children/617782>\
**Category:** Factual Questions\
**Created:** [April 4, 2012, 6:23am UTC](https://boards.straightdope.com/t/mongolian-spot-common-on-mixed-race-children/617782 "2012-04-04T06:23:17Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![grude](https://avatars.discourse-cdn.com/v4/letter/g/e47774/32.png) [@grude](https://boards.straightdope.com/u/grude)\
**Post date:** [April 4, 2012, 6:23am UTC](https://boards.straightdope.com/t/mongolian-spot-common-on-mixed-race-children/617782/1 "2012-04-04T06:23:17Z")

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My son was born with a Mongolian spot which has faded:

> **[Mongolian spot](https://en.wikipedia.org/wiki/Mongolian_spot)**
>
> A Mongolian spot, also known as slate grey nevus or congenital dermal melanocytosis, is a benign, flat, congenital birthmark with wavy borders and an irregular shape. In 1883, it was described and named after Mongolians by Erwin Bälz, a German anthropologist based in Japan, who erroneously believed it to be most prevalent among his Mongolian patients. It normally disappears three to five years after birth and almost always by puberty. The most common color is blue, although they can b Mongolian s...

The article has the incidence rate for various racial groups but doesn’t mention anything about mixed race.

My son’s pediatrician made an odd comment when we mentioned we looked it up because it was unfamiliar to either of us, she said she wasn’t surprised as she mostly sees it in mixed race children and nearly all her mixed race patients have it.

Is that true?

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**Author:** ![JKellyMap](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jkellymap/32/15880_2.png) [@JKellyMap](https://boards.straightdope.com/u/JKellyMap)\
**Post date:** [April 4, 2012, 8:31am UTC](https://boards.straightdope.com/t/mongolian-spot-common-on-mixed-race-children/617782/2 "2012-04-04T08:31:58Z")

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Our son was also born with one which has now mostly faded, and he has one white-skinned parent (Euro-American) and one dark-skinned one (Dravidian Indian). Our pediatrician also told us it’s common in babies with parents of contrasting skin colors (not exactly “mixed race” per se, which can be a more ambiguous term).

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**Author:** ![Broomstick](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/broomstick/32/246_2.png) [@Broomstick](https://boards.straightdope.com/u/Broomstick)\
**Post date:** [April 4, 2012, 10:39am UTC](https://boards.straightdope.com/t/mongolian-spot-common-on-mixed-race-children/617782/3 "2012-04-04T10:39:20Z")

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Given that the incidence of this in Europeans who _aren’t_ mixed race is as high as 40-45% I’m not sure why the appearance of a Mongolian Spot in people of “mixed race” would surprise anyone. Given the prevalence of it elsewhere in the world I’d think the _lack_ of it in Europeans would actually be more noteworthy except, of course, most of us here lived in a Caucasian-dominated culture.

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**Author:** ![FluffyBob](https://avatars.discourse-cdn.com/v4/letter/f/ecb155/32.png) [@FluffyBob](https://boards.straightdope.com/u/FluffyBob)\
**Post date:** [April 4, 2012, 1:11pm UTC](https://boards.straightdope.com/t/mongolian-spot-common-on-mixed-race-children/617782/4 "2012-04-04T13:11:02Z")

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I think race is pretty hard to define by such things when it really comes down to it. My sister and I both were born with it. A few generations back we are supposed to have a Native American ancestor. I suspect that most north americans whose family history goes back to times of colonization are going to have some native american ancestry.