New Insights into Clonality and Panmixia in Plasmodium and Toxoplasma

Is Predominant Clonal Evolution a Common Evolutionary Adaptation to Parasitism in Pathogenic Parasitic Protozoa, Fungi, Bacteria, and Viruses?

“…This has been corroborated by further studies (Sibley and Boothroyd, 1992). The three main clonal lineages recorded by various authors (Beck et al, 2009;Boothroyd, 2009;Rajendran et al, 2012;Sibley and Ajioka, 2008;Sibley and Boothroyd, 1992;Smith, 2009;Su et al, 2010), which predominate in European and North American domestic cycles, correspond to typical near-clades (Tibayrenc and Ayala, 2014a), corroborated by various markers and software. Clustering of antigen genes parallels that of introns (Khan et al, 2011).…”

“…It includes, not only mitotic clonality but also all cases where recombination is rare or absent (Tibayrenc et al, 1990), such as several cases of parthenogenesis, gynogenesis and hybridogenesis (Avise, 2004(Avise, , 2008(Avise, , 2015, as well as self-fertilization in homozygous states, strong inbreeding and 'unisexuality' . As we have shown (Tibayrenc and Ayala, 2012, 2013, 2014a, this definition is widely used by researchers working on population genetics of all kinds of micropathogens (Table 2). It is also accepted by scientists working on unisexual vertebrates (Avise, 2004(Avise, , 2008(Avise, , 2015.…”

“…Indeed, highresolution typing of no less than 956 strains collected worldwide based on PCRerestriction fragment length polymorphism (RFLP), intron sequences of housekeeping genes and microsatellites reveals that this parasite's overall population structure (including South America) exhibits deep phylogenies and is composed of 6 'major clades' (near-clades) . Among the six clades described by Su et al (2012), three of them (clades A, B and F) exhibit RD patterns, with LD and additional near-clades within each of them (Tibayrenc and Ayala, 2014a). An RD pattern is also observed within the near-clade 'haplogroup 12', with strong LD and overrepresented MLGs (Khan et al, 2011).…”

“…We argue that it is not the case for the PCE model, which is easy to understand, as we have been able to verify it with many non-specialists. It relies on the direct observation of abundant data that can be easily verified by anybody, the main ones being presented later (see also Tibayrenc and Ayala, 2012, 2013, 2014a.…”

“…The predominant clonal evolution (PCE) model proposed by us (Tibayrenc et al, 1990;Tibayrenc and Ayala, 2012, 2013, 2014a includes several specific assumptions that deserve to be recalled, because they are frequently misunderstood or misquoted.…”