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THEORY VS PRACTICE 1. "If one assumes that the ancestral angiosperm chromosome number is 5–7, as often suggested, then modern Gossypium hirsutum, for example, should have 5–7 times 144, or 720–1008 chromosomes in its haploid complement, in the absence of massive, repeated chromosome number reduction, instead of the 26 it actually contains." http://www.amjbot.org/content/early/2015/10/09/ajb.1500320 View in LinkedIn

CONSEQUENCES. "Some of the longer-term consequences of repeated, cyclical polyploidy become evident when one considers that lineages having experienced multiple historical rounds of polyploidy do not exhibit especially high chromosome numbers nor genome sizes." http://www.amjbot.org/content/early/2015/10/09/ajb.1500320 View in LinkedIn

CASCADE OF TRAITS. "Even more varied yet poorly understood is the gamut of short-term evolutionary responses to polyploidy at other “omics” levels, including a diverse suite of epigenomic and small RNA alterations with cascading effects that propagate through proteomic, physiological, and metabolomic networks to ultimately affect plant phenotype and function." http://www.amjbot.org/content/early/2015/10/09/ajb.1500320 View in LinkedIn

NEW TRAITS. "New and young polyploids typically display novel transcriptomic and/or proteomic phenomena, including biased gene expression with respect to homoeolog (duplicate gene copies resulting from polyploidy), expression level dominance with respect to the two different progenitor diploid genomes, and expression subfunctionalization (partitioning of aggregate ancestral expression among homoeologs) or neofunctionalization (novel expression domain or protein function)." http://www.amjbot.org/content/early/2015/10/09/ajb.1500320 View in LinkedIn

TIP OF THE ICEBERG. "The scale and scope of these phenomena vary among systems, genes, and genomic regions, and in most cases there is little understanding of phenotypic consequence or ecological or evolutionary significance." http://www.amjbot.org/content/early/2015/10/09/ajb.1500320 View in LinkedIn

DUPLICATION CONSEQUENCES. "Responses at the genomic (DNA) level include mutagenic gene silencing or deletional loss, intergenomic transfer of repetitive elements such as transposable elements, differential rates of accumulation of synonymous or nonsynonymous nucleotide substitutions, and various forms of homoeologous (duplicated copies generated by polyploidy) interaction or gene conversion that generate sequences chimeras or duplicated genes (shown as “recombination”)." http://www.amjbot.org/content/early/2015/10/09/ajb.1500320 View in LinkedIn

OBSCURED BY DIVERSITY. "Why was it not classically recognized? The answer to this question lies in the equally surprising spectrum of genomic processes set in motion by polyploidy." http://www.amjbot.org/content/early/2015/10/09/ajb.1500320 View in LinkedIn

DEEP CONSEQUENCES. "This genome multiplicity is an extraordinary realization, with myriad implications for our understanding of genomic architecture, plant gene family structure, and plant function." http://www.amjbot.org/content/early/2015/10/09/ajb.1500320 View in LinkedIn

RANGE OF MULTIPLICATIONS. "Writ large, over the grand sweep of angiosperm history, we now understand that modern angiosperm genomes range in genomic complexity from those that have experienced few genomic multiplication events (e.g., Amborella, Allium, Olea, Theobroma) to others that reflect as many as 128 (Saccharum), 144 (Gossypium), and even 288 (Brassica) genomic multiples." http://www.amjbot.org/content/early/2015/10/09/ajb.1500320 View in LinkedIn

ORIGIN OF PLOIDY. "Polyploids are known to originate within individuals, or following hybridization between closely related populations (auto-polyploidy), or from interspecific hybridization events (allopolyploidy)." http://www.amjbot.org/content/early/2015/10/09/ajb.1500320 View in LinkedIn