Thirty plants were collected in 15 villages in Benin (Additional file 2: Table S1). Sampling included 10 individuals belonging to the cultivated species D. rotundata, and 10 individuals belonging to each of its two closest wild relatives, D. abyssinica and D. praehensilis. Plants were identified by Serge Tostain (yam specialist, IRD), Nora Scarcelli (yam specialist, IRD) and local yam farmers. DNA was extracted as previously described using a standard protocol . Genomic libraries were constructed using a recent protocol . The genomic libraries were 2 × 100 bp paired-end sequenced by sample multiplexing using the Illumina HiSeq 2000 technology (GeT_Genotoul, Toulouse, France).