Microsatellite analyses
Allele dropout and stuttering measures were not significant and the
presence of null alleles was indicated for all loci. Genotyping error
was estimated to be 1.55%. Most pairwise comparisons indicated
significant deviation from Hardy-Weinberg equilibrium (Supporting
Information 3) and linkage disequilibrium (Supporting Information 4)
after FDR corrections.
The DAPC (Fig. 1) presented clear structure composed by four populations
(BRA+BP2+COL+ARG+URU; SIN+CUB; CHI+KOR+BEL; JAP). There is almost
complete overlap among all South American countries, hereafter referred
as Population 1 (Pop1), including the two populations described in
Brazil (Jorgewich-Cohen et al., in press). Population 1 has a marginal
link with Cuba, which is almost completely overlapped with samples from
Singapore, together forming Population 2 (Pop2). Samples from the
Republic of Korea, Belgium and China are also greatly overlapped and
were considered as one unit (Pop3). Japan is completely isolated and was
considered as a separated population (Pop4). Calculation of pairwise
Jost’s D index values (Table 1) revealed greater differentiation between
Pop3 and all others. The smallest differentiation reveled is between
Pop2 and Pop4, followed by the differentiation between Pop1 and Pop2.
The differentiation between pairs of populations was always significant
(p=0.001). With exception for Pop2, the observed heterozygosity (Ho) did
not match expected heterozygosity (He) and both populations showed
positive inbreeding values (Supporting Information 3).