A friend of mine asked me a old question (I am really interested in) on FaceBook, which sparks me to dig the web again. These are some of mine findings.
A Mongolian spot/mark(蒙古斑), which appears on many baby buttock during birth, few carry it till grown up, most will not have it when or around five. The interesting part I read is in Wikipedia. It says,
"Mongolian spots are most prevalent among Mongols, Turks, and other Asian groups, such as the Chinese, Japanese, and Koreans. Nearly all East Asian infants are born with one or more Mongolian spots. It is also common if only one of the parents is East Asian. Among East African infants it is found at rates between 90-95% and 85-90% of Native American infants."
Dr Greene said on his site,
"Mongolian spots are nothing more than dense collections of melanocytes, the skin cells which contain melanin, the normal pigment of the skin. When the melanocytes are close to the surface, they look deep brown."
If your family carries at least one Asian Heritage, most likely you have it, or seen it. If this means you carry the blood of Mongolian, I think 85% of the world came from a same blood.
This Genetic blue mark, also has some spiritual/religious legend. On Media Thinker's 2003 post,
"The Mongols say they are the mark left by the spirit who slaps the baby to life. Chinese believe that if you are reluctant to be reincarnated, the King of Hell prods and kicks you until you agree to go. The more spots, the more reluctant you were to be reborn."
If you would like to find out more, I recommend a visit to Alive in Kyoto's post - Mongolian Blue Spot. More than a dozen comment there. Commenter barb raise an interesting question there:
"Does anyone know if there is biblical side to the mongolian spot?"
Tell me here if you find out more..
More read - Asia Finest Forum: Mongolian Blue Spot