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Using next-generation sequencing technology alone, we have successfully generated and assembled a draft sequence of the giant panda genome. The assembled contigs (2.25 gigabases (Gb)) cover approximately 94% of the whole genome, and the remaining gaps (0.05 Gb) seem to contain carnivore-specific repeats and tandem repeats. Comparisons with the dog and human showed that the panda genome has a lower divergence rate. The assessment of panda genes potentially underlying some of its unique traits indicated that its bamboo diet might be more dependent on its gut microbiome than its own genetic composition. We also identified more than 2.7 million heterozygous single nucleotide polymorphisms in the diploid genome. Our data and analyses provide a foundation for promoting mammalian genetic research, and demonstrate the feasibility for using next-generation sequencing technologies for accurate, cost-effective and rapid de novo assembly of large eukaryotic genomes. [ABSTRACT FROM AUTHOR]

Here we integrate the de novo assembly of an Asian and an African genome with the NCBI reference human genome, as a step toward constructing the human pan-genome. We identified ∼5 Mb of novel sequences not present in the reference genome in each of these assemblies. Most novel sequences are individual or population specific, as revealed by their comparison to all available human DNA sequence and by PCR validation using the human genome diversity cell line panel. We found novel sequences present in patterns consistent with known human migration paths. Cross-species conservation analysis of predicted genes indicated that the novel sequences contain potentially functional coding regions. We estimate that a complete human pan-genome would contain ∼19–40 Mb of novel sequence not present in the extant reference genome. The extensive amount of novel sequence contributing to the genetic variation of the pan-genome indicates the importance of using complete genome sequencing and de novo assembly. [ABSTRACT FROM AUTHOR]

Cucumber is an economically important crop as well as a model system for sex determination studies and plant vascular biology. Here we report the draft genome sequence of Cucumis sativus var. sativus L., assembled using a novel combination of traditional Sanger and next-generation Illumina GA sequencing technologies to obtain 72.2-fold genome coverage. The absence of recent whole-genome duplication, along with the presence of few tandem duplications, explains the small number of genes in the cucumber. Our study establishes that five of the cucumber's seven chromosomes arose from fusions of ten ancestral chromosomes after divergence from Cucumis melo. The sequenced cucumber genome affords insight into traits such as its sex expression, disease resistance, biosynthesis of cucurbitacin and 'fresh green' odor. We also identify 686 gene clusters related to phloem function. The cucumber genome provides a valuable resource for developing elite cultivars and for studying the evolution and function of the plant vascular system. [ABSTRACT FROM AUTHOR]