The impact of Converso Jews on the genomes of modern Latin Americans

Abstract

Modern day Latin America resulted from the encounter of Europeans with the indigenous peoples of the Americas in 1492, followed by waves of migration from Europe and Africa. As a result, the genomic structure of present day Latin Americans was determined both by the genetic structure of the founding populations and the numbers of migrants from these different populations. Here, we analyzed DNA collected from two well-established communities in Colorado (33 unrelated individuals) and Ecuador (20 unrelated individuals) with a measurable prevalence of the BRCA1 c.185delAG and the GHR c.E180 mutations, respectively, using Affymetrix Genome-wide Human SNP 6.0 arrays to identify their ancestry. These mutations are thought to have been brought to these communities by Sephardic Jewish progenitors. Principal component analysis and clustering methods were employed to determine the genome-wide patterns of continental ancestry within both populations using single nucleotide polymorphisms, complemented by determination of Y-chromosomal and mitochondrial DNA haplotypes. When examining the presumed European component of these two communities, we demonstrate enrichment for Sephardic Jewish ancestry not only for these mutations, but also for other segments as well. Although comparison of both groups to a reference Hispanic/Latino population of Mexicans demonstrated proximity and similarity to other modern day communities derived from a European and Native American two-way admixture, identity-by-descent and Y-chromosome mapping demonstrated signatures of Sephardim in both communities. These findings are consistent with historical accounts of Jewish migration from the realms that comprise modern Spain and Portugal during the Age of Discovery. More importantly, they provide a rationale for the occurrence of mutations typically associated with the Jewish Diaspora in Latin American communities.

The Genetic Diversity of the Americas

“…Although recent converts were not legally permitted to travel to the New World, it has been argued that many in fact made the journey. Interestingly, the analysis of Y chromosome data and rare disease mutations are consistent with a genetic contribution from North Africa and the Middle East to the ancestry of Ibero-Americans (15,26,35,65,100).…”

Haplotype analysis of the 185delAG BRCA1 mutation in ethnically diverse populations

“…The estimated contribution of Jewish linage in the current-day inhabitants of the Iberian Peninsula is estimated at 20%, 37 and the contribution and existence of Sephardic Jews is also noted in South American communities. 38 The age at which the mutation arose in the Hispanics, and the shared haplotype with Ashkenazim, is in line with these historic events, as well as with the specific history of the establishment of the New Mexico Colony in 1598 and descendants to the San Luis Valley in 1850. 20,35 The Jewish Ashkenazi 185delAG*BRCA1 mutation carriers all share a common haplotype, supporting the founder mutation theory.…”

Prevalence and Type ofBRCAMutations in Hispanics Undergoing Genetic Cancer Risk Assessment in the Southwestern United States: A Report From the Clinical Cancer Genetics Community Research Network

“…44 Eighteen probands had a BRCA1 185delAG, a known Jewish founder mutation, in our Hispanic population (9.5% of BRCA carriers). The term Hispanos has been applied to the Colonial-Hispanic population 45 in the San Luis Valley, encompassing parts of Colorado and New Mexico, and it is suggested that their ancestral origins stem from the immigration of Spanish Conversos and Crypto-Jews. 46 Although five 185delAG carriers in our study were from New Mexico, and thus likely Hispanos, they reported grandparental ancestry as Mexican or Spanish.…”