Southeast Asian mitochondrial DNA analysis reveals genetic continuity of ancient mongoloid migrations.

Abstract

Human mitochondrial DNAs (mtDNAs) from 153 independent samples encompassing seven Asian populations were surveyed for sequence variation using the polymerase chain reaction (PCR), restriction endonuclease analysis and oligonucleotide hybridization. All Asian populations were found to share two ancient AluI/DdeI polymorphisms at nps 10394 and 10397 and to be genetically similar indicating that they share a common ancestry. The greatest mtDNA diversity and the highest frequency of mtDNAs with HpaI/HincII morph 1 were observed in the Vietnamese suggesting a Southern Mongoloid origin of Asians. Remnants of the founding populations of Papua New Guinea (PNG) were found in Malaysia, and a marked frequency cline for the COII/tRNA(Lys) intergenic deletion was observed along coastal Asia. Phylogenetic analysis indicates that both insertion and deletion mutations in the COII/tRNA(Lys) region have occurred more than once.

Genetic studies of human diversity in East Asia

“…The north-south division raises the question of whether the southern and northern East Asians ( NEAS) are descendants of the same ancestral population in East Asia or originated from different populations that arrived in East Asia via different routes. To date, three main hypotheses have been brought forward on the entry of modern humans into East Asia: (i) entry from Southeast Asia followed by northward migrations (Turner 1987;Ballinger et al 1992;Chu et al 1998;Su et al 1999;Yao et al 2002;Shi et al 2005), (ii) entry from northern Asia followed by southward migrations (Nei & Roychoudhury 1993), and (iii) southern and NEAS are derived from different ancestral populations, i.e. southern populations from Southeast Asia and northern populations from Central Asia (Cavalli-Sforza et al 1994;Xiao et al 2000;Karafet et al 2001).…”

The History and Diversity of Rice Domestication as Resolved From 1464 Complete Plastid Genomes

“…However organellar genomes (in particular plastids) possess several advantageous qualities in the inference of crop origin and diversity including high copy number, which is useful in degraded archeological finds ( Schlumbaum et al, 2008 ; Wagner et al, 2018 ), uniparental inheritance resulting in more recent inferences for coalescence times ( Palumbi et al, 2001 ), lack of recombination reducing problems associated with introgression and incomplete lineage sorting ( Hu et al, 2016 ), and a variable mutation rate which is useful for inferences at multiple taxonomic levels ( Pollmann et al, 2005 ). There are numerous well-known examples using organellar DNA in studies of origin, dispersal, and diversity, like the resolution of our own human history using mitochondrial DNA ( Ballinger et al, 1992 ; Forster et al, 2001 ; Tanaka et al, 2004 ) and the use of plastid DNA as a standard phylogenetic marker in the Angiosperm Phylogeny Group (APG) classification of flowering plant orders and families ( Byng et al, 2016 ). Therefore, pangenomic approaches to plastomic DNA analyses are expected to provide useful insights into the origin, and diversity of numerous domesticated crop species.…”

Do mitochondria recombine in humans?

“…Mitochondrial DNA has also been used to trace the patterns of human migration across the world. The technique has been particularly successful in illuminating the way in which the Americas were colonized by successive waves of native Siberians (Torroni et al 1992(Torroni et al , 1993. Although it is expected that the interpretation of much of this work will remain una¡ected if mtDNA is not clonal, recombination might have some subtle and important e¡ects.…”