Alu insertion polymorphisms in Native Americans and related Asian populations.
BACKGROUND
Alu insertions provide useful markers for the study of inter-population affinities and historical processes, but data on these systems are not numerous in Native Americans and related populations.


OBJECTIVE
The study aimed to answer the following questions: (a) do the population relationships found agree with ethnic, historical and geographical data? and (b) what can heterozygote levels and associated results inform us about the events that led to the colonization of the New World?


METHODS
Twelve Alu insertion polymorphisms were studied in 330 individuals belonging to South American Native, Siberian and Mongolian populations. These data were integrated with those from 526 persons, to ascertain the relationships between Asian, Northern Arctic and Amerindian populations.


RESULTS
A decreasing trend concerning heterozygosities and amount of gene flow was observed in the three sets, in the order indicated above. Most results indicated the validity of these subdivisions. However, no clear structure could be observed within South American Natives, indicating the importance of dispersive (genetic drift, founder effects) factors in their differentiation.


CONCLUSIONS
The answers to the questions are: (a) yes; and (b) an initial moderate bottleneck, intensified by more recent historical events (isolation and inbreeding), can explain the current Amerindian pattern of diversity.
Battilana
Jaqueline
J
Centro de Biologia Genômica e Molecular, Pontifícia Universidade Católica do Rio Grande do Sul, Faculdade de Biociências, Porto Alegre, RS, Brazil.
Fagundes
Nelson J R
NJ
Heller
Ana H
AH
Goldani
Angela
A
Freitas
Loreta B
LB
Tarazona-Santos
Eduardo
E
Munkhbat
Batmunkh
B
Munkhtuvshin
Namid
N
Krylov
Mlu
M
Benevolenskaia
Lidia
L
Arnett
Frank C
FC
Batzer
Mark A
MA
Deininger
Prescott L
PL
Salzano
Francisco M
FM
Bonatto
Sandro L
SL