The genome of Theobroma cacao

Nature Genetics (Impact Factor: 29.35). 01/2011; 34(2):101-109. DOI: 10.1038/npre.2010.4908.1
Source: OAI


We sequenced and assembled the genome of Theobroma cacao, an economically important tropical fruit tree crop that is the source of chocolate. The assembly corresponds to 76% of the estimated genome size and contains almost all previously described genes, with 82% of them anchored on the 10 T. cacao chromosomes. Analysis of this sequence information highlighted specific expansion of some gene families during evolution, for example flavonoid-related genes. It also provides a major source of candidate genes for T. cacao disease resistance and quality improvement. Based on the inferred paleohistory of the T. cacao genome, we propose an evolutionary scenario whereby the ten T. cacao chromosomes were shaped from an ancestor through eleven chromosome fusions. The T. cacao genome can be considered as a simple living relic of higher plant evolution.

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Available from: Spencer Craig Brown, Dec 13, 2013
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    • "ransposons ( i . e . non - autonomous , poss - ibly nested , defective or inactive ) , though similar estimates have been reported for other plants . The genome of cocoa tree , Theobroma cacao , was estimated to contain approximately 6 . 75 £ 10 4 copies of trans - posable elements , although this estimate was regarded as a rough underestimation ( Argout et al . , 2011 ) . The genome of Populus trichocarpa has over 5000 copies of retrotransposons with a prevalence of Gypsy - like elements ( Tuskan et al . , 2006 ) ; recently , 1479 full - length LTR retrotransposons were identified in poplar ( Cossu et al . , 2012 ) . In Eucalyptus , 24 – 226 copies of trans - criptionally active Copia - like LTR retr"
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