Skip to main content
Premium Trial:

Request an Annual Quote

Nature Papers Present Gala Apple Genome, Genome Analysis Tracks Coronavirus Spread in Israel, More

High-quality, phased diploid genomes for the cultivated Gala apple and two of its wild relatives are reported in Nature Genetics this week, offering insights into the genetic basis of apple domestication. In the study, a team led by scientists from the Boyce Thompson Institute assemble haplotype-resolved genomes for the Gala, a popular cultivar that is frequently used as a parental line in apple breeding, and the wild progenitors Malus sieversii and Malus sylvestris. They directly sequenced the heterozygous lines and disclosed the diploid state of the genomes, then constructed pan-genomes for each of the apple species using 91 deeply resequenced accessions to reveal new trait-associated genes. These resources, the researchers write, are expected to assist in future apple research and breeding efforts.

By analyzing hundreds of full SARS-CoV-2 genome sequences, a Tel Aviv University-led research group has tracked the spread of the virus into and throughout Israel, highlighting the importance of border control and shelter-in-place restrictions to outbreak containment. The scientists sequenced 212 SARS-CoV-2 samples from across Israel and used the results to track the virus. They found that travelers returning from the US played an outsized role in spreading the virus in Israel and used phylodynamic analysis to determine that viral reproduction rates fell by more than two-thirds following the rollout of social distancing measures. The investigators also report that between 5 percent and 10 percent of infected individuals were responsible for 80 percent of secondary infections. "Our results indicate that superspreading events drive the transmission dynamics of SARS-CoV-2, suggesting that focused measures to reduce contacts of select individuals/social events could mitigate viral spread," they write.

A molecular tagging method based on DNA sequencing is described by a University of Washington team in this week's Nature Communications. Called Porcupine, the molecular tagging system uses synthetic DNA-based tags that are readable within seconds using a portable nanopore device. The system's digital bits are represented by the presence or absence of distinct DNA strands — dubbed molecular bits, or molbits — that are classified directly from raw nanopore signals, avoiding basecalling. Molbits are also prepared for readout during tag assembly and can be stabilized by dehydration to extend shelf life, decrease readout time, and make the tags resistant to environmental contamination, the technology's developers write.