Table 1 Prior distributions and description of the parameters used in the simulations

T

Admixture time between NEA and SEA under two-route models (in generations)

1 to 2,500

Between 0 and 65,000 years (estimation of the spread of modern humans in East Asia [5]), each generation representing 25 years

A

Number of initial lineages in the source population

10 to 50

Numbers of HLA−A, −B and −DRB1 lineages vary between 10 and 40 in East Asian samples (from data listed in Additional file 1: Table S1)

N

Maximum population density of one deme

0 to 5,000

According to the estimation of hunter-gatherer densities at the end of Paleolithic (0-0.4 individuals per km ² [18]

m

Population migration rate of one deme

0.01 to 0.20

Between 1 % and 20 % of emigration per generation [18]

r

Population growth rate of one deme

0.01 to 0.20

According to the estimation of growth rate for Paleolithic populations [18]

s

Coefficient of balancing selection

0 to 0.025

Selection rate higher than 2.5 % was tested by preliminary simulations but it never lead to the reproduction of observed data [40–42]