FURTHER EVIDENCE FOR THE EXISTENCE OF A MAJOR FOUNDER Y-CHROMOSOME HAPLOTYPE IN AMERINDIANS

We haplotyped human Y-chromosomes with two different PCR-based DNA pol ymorphisms. The first was the tetranucleotide microsatellite DYS19 (Y- 27H39) while the other was based on sequence variation in alphoid repe ats located in the Y centromeric region, typed by heteroduplex analysi s. There are 23 different alphoid haplotypes (ah) that, together with DYS19, enable us to distinguish at least 37 different Y-chromosome hap lotypes worldwide. Previously we studied 12 different Amerindian popul ations of diverse geographical origins (ranging from Argentina to Mexi co) and from several linguistic groups. The haplotype IIA (combination of ah II and DYS19 allele A) was seen in the great majority of the in dividuals studied. We describe here results for 37 further Amerindians belonging to five tribes from the Amazon Basin and Central Brazil. Ag ain, haplotype IIA was found in most individuals (87%), thus confirmin g its nature as a major, perhaps single, founder haplotype of Amerindi ans.