The mulberry colored spot is very well known in Afro-Brazilians. In Brazil, among individuals of mixed Indigenous American and West African descent (pardo) it is called "genipapo", from its resemblance in color (bluish-gray) to an indigenous fruit of Brazil, named genipapo (a Native word adopted into Portuguese). Prevalence
Infants may be born with one or more slate grey nevus ranging from small area on the buttocks to a larger area on the back. The birthmark is prevalent among East, South, Southeast, North and Central Asian peoples, Indigenous Oceanians (chiefly Micronesians and Polynesians), certain populations in Africa, Amerindians, non-European Latin Americans and Caribbeans of mixed-race descent.They occur in around 80% of Asians, and 80% to 85% of Native American infants. Approximately 90% of Polynesians and Micronesians are born with slate grey nevus, as are about 46% of children in Latin America, where they are associated with non-European descent. These spots also appear on 5–10% of babies of full Caucasian descent; Coria del Río in Spain has a high incidence due to the presence of descendants of members of the delegation led by Hasekura Tsunenaga, the first Japanese official envoy to Spain in the early 17th century. African American babies have slate grey nevus at a frequencies of 90% to 96%.According to a 2006 study examining the Mongolian spot among newborns in the Turkish city of İzmir, it was found out that 26% of the examined babies had the condition. It was noted the prevalence rate was 20% and 31% in boys and girls, respectively.
It was Erwin Bälz, a German working in Tokyo, who described a dark blue mark on Japanese infants. He presented his findings in 1901 in Berlin, and from that point on, Bälzs name was associated with certain skin cells containing pigment. Captain Gustav Frederik Holm wrote in 1887 that his Greenlandic interpreter Johannes Hansen (known as Hanserak) attested to the existence of the birthmark over the kidney region of newborns, which grows larger as they grow older. That year, the Danish anthropologist Soren Hansen drew the connection between the observations of Bälz in Japan and Saabye in Greenland. "This cannot be a coincidence. It is not the first time that the resemblance between the Japanese and the Eskimo has been pointed out." Fridtjof Nansen, the Norwegian polar explorer, said that the spot was widespread in the mixed Danish-Inuit population of West Greenland. Soren Hansen confirmed this. A missionary in Bethel, Alaska, a traditional gathering place of Yupik people, reported that the spots were common on children. Rudolf Trebitsch, an Austrian linguist and ethnologist, spent the summer of 1906 on the West Coast of Greenland, and listed all the examples he came across. Gessain went to north Labrador in 1926, looking for children with these spots.