Analysis of Y-chromosome and mtDNA variability in the Madeira Archipelago population

The Atlantic archipelago of Madeira is made up of two islands (Madeira and Porto Santo) with 250,000 inhabitants. These islands were discovered and settled by the Portuguese in the 15th century and played an important role in the complex Atlantic trade network in the following centuries. The genetic composition of the Madeira Islands’ population was investigated by analyzing Y-chromosomal bi-allelic and STR markers in three different regions of the main island plus Porto Santo. We compared the results with mtDNA data and used the Y-chromosome STRs to determine the variability within each haplogroup. A sample of 142 unrelated males divided into four groups (Funchal City, West Madeira, North and East Madeira and Porto Santo) were analyzed. Significant genetic differences between these regions and the population of Funchal were found. The population of Funchal had lower gene diversity than expected.