Can International Boycotts Transform Political Systems? The Cases of Cuba and South Africa

The economic embargo against Cuba has been widely promoted as a way to hasten the end of the Castro regime. Historically, however, the connection between embargoes and regime change is mediated by a complex of political, social, and economic conditions. Labormarket bottlenecks and domestic elite opposition, decisive factors in the South African case, are absent from that of Cuba. This study uses the factors derived from an analysis of South Africa to compare the Cuban case and concludes that the embargo against Cuba cannot have its intended results.     

Correlation of surnames and Y-chromosome in Central-Brazil

In patrilineal societies, surnames and Y-specific haplotypes and haplogroups are expected to be correlated. This characteristic could help defining an initial pool of suspects in forensic genetics analysis. Here we evaluated this correlation in a sample of Central-Brazilian men. Surnames and Y-SNP haplogroup and Y-STR haplotype were analyzed in 55 pairs of Central-Brazilian men sharing surnames (n = 110). Seven haplogroups and thirty-two haplotypes have been observed, none correlated solely to any of the twenty-eight surnames represented here. In this sample, two men with the same surname showed a chance of 0.41 of sharing a Y-specific haplogroup. This chance is higher for surnames of intermediate frequencies, whereas rare surnames show distinct chances as zero and one. Observed results may be over-estimated due to a predominance of a specific haplogroup (P92R7 = 49%) in the sample, what makes it possible for two men with no coancestry to share this haplogroup. Considering STR, only three pairs of men shared haplotypes. The average difference between the haplotypes in each pair was 2.45 mutational steps. This relatively low correlation is due to some historical and cultural peculiarities of the country, what makes it improper for forensic purposes in Brazil.     

Inferring ancestral origin using a single multiplex assay of ancestry-informative marker SNPs

Tests that infer the ancestral origin of a DNA sample have considerable potential in the development of forensic tools that can help to guide crime investigation. We have developed a single-tube 34-plex SNP assay for the assignment of ancestral origin by choosing ancestry-informative markers (AIMs) exhibiting highly contrasting allele frequency distributions between the three major population-groups. To predict ancestral origin from the profiles obtained, a classification algorithm was developed based on maximum likelihood. Sampling of two populations each from African, European and East Asian groups provided training sets for the algorithm and this was tested using the CEPH Human Genome Diversity Panel. We detected negligible theoretical and practical error for assignments to one of the three groups analyzed with consistently high classification probabilities, even when using reduced subsets of SNPs. This study shows that by choosing SNPs exhibiting marked allele frequency differences between population-groups a practical forensic test for assigning the most likely ancestry can be achieved from a single multiplexed assay.