The impact of recent events on human genetic diversity
Mark A. Jobling
Department of Genetics, University of Leicester, University Road, Leicester LE1 7RH, UK .
The historical record tells us stories of migrations, population expansions and colonization events in the last few thousand years, but what was their demographic impact? Genetics can throw light on this issue, and has mostly done so through the maternally inherited mitochondrial DNA (mtDNA) and the male-speciﬁc Y chromosome. However, there are a number of problems, including marker ascertainment bias, possible inﬂuences of natural selection, and the obscuring layers of the palimpsest of historical and prehistorical events.
Y-chromosomal lineages are particularly affected by genetic drift, which can be accentuated by recent social selection. A diversity of approaches to expansions in Europe is yielding insights into the histories of Phoenicians, Roma, Anglo-Saxons and Vikings, and new methods for producing and analysing genome-wide data hold much promise.
The ﬁeld would beneﬁt from more consensus on appropriate methods, and better communication between geneticists and experts in other disciplines, such as history, archaeology and linguistics.