. 2007 Feb 13;3(2):218–223. doi: 10.1098/rsbl.2006.0609

Table 2.

Average frequency of 9RA in linguistic and geographical groups.

linguistic/geographical group	populations sampled	average population frequency of 9RA
Aleut-Eskimo	Aleut and Inuit	0.308
Na-Dene	Dogrib and Apache	0.311
Amerind	Cherokee, Chippewa, Huichol, Mixtec, Northern Paiute, Sioux, Seri, Jemez, Creek, Colombian, Karitiana, Surui, Maya and Pima	0.335^a
Western Beringia	Chukchi and Koryaks	0.207
North America	Aleut, Inuit, Dogrib, Apache, Cherokee, Chippewa, Huichol, Mixtec, Northern Paiute, Sioux, Seri, Jemez, Creek, Maya and Pima	0.301^a
South America	Colombian, Karitiana and Surui	0.471^a

When the Seri and the Surui are excluded, the frequencies of 9RA in the Amerind, North America and South America are 30.1, 31.5 and 22.1%, respectively.