RT Journal
A1 Wangkumhang, Pongsakorn
A1 Greenfield, Matthew
A1 Hellenthal, Garrett
T1 An efficient method to identify, date, and describe admixture events using haplotype information
JF Genome Research 
JO Genome Research 
YR 2022 
FD August 01 
VO 32 
IS 8 
SP 1553 
OP 1564 
DO 10.1101/gr.275994.121 
UL http://genome.cshlp.org/content/32/8/1553.abstract 
AB We present fastGLOBETROTTER, an efficient new haplotype-based technique to identify, date, and describe admixture events using genome-wide autosomal data. With simulations, we show how fastGLOBETROTTER reduces computation time by an order of magnitude relative to the related technique GLOBETROTTER without suffering loss of accuracy. We apply fastGLOBETROTTER to a cohort of more than 6000 Europeans from 10 countries, revealing previously unreported admixture signals. In particular, we infer multiple periods of admixture related to East Asian or Siberian-like sources, starting >2000 yr ago, in people living in countries north of the Baltic Sea. In contrast, we infer admixture related to West Asian, North African, and/or Southern European sources in populations south of the Baltic Sea, including admixture dated to ∼300–700 CE, overlapping the fall of the Roman Empire, in people from Belgium, France, and parts of Germany. Our new approach scales to analyzing hundreds to thousands of individuals from a putatively admixed population and, hence, is applicable to emerging large-scale cohorts of genetically homogeneous populations.