Polymorphic Alu insertions and the Asian origin of Native American populations.

A rapid PCR-based assay was used to study the distribution of 5 polymorphic Alu insertions in 895 unrelated individuals from 30 populations, 24 from North, Central, and South America. Although a significant level of interpopulation variability was detected, the variability was less than that observed in a worldwide population survey. This is consistent with the bottleneck effect and genetic drift forces that may have acted on the migrating founder groups. The results corroborate the Asian origin of native American populations but do not support the multiple-wave migration hypothesis supposedly responsible for the tri-partite Eskaleut, Nadene, and Amerind linguistic groups. Instead, these populations exhibit three major identifiable clusters reflecting geographic distribution. Close similarity between the Chinese and native Americans suggests recent gene flow from Asia.