RESUMO
Sugarcane, the world's most harvested crop by tonnage, has shaped global history, trade and geopolitics, and is currently responsible for 80% of sugar production worldwide1. While traditional sugarcane breeding methods have effectively generated cultivars adapted to new environments and pathogens, sugar yield improvements have recently plateaued2. The cessation of yield gains may be due to limited genetic diversity within breeding populations, long breeding cycles and the complexity of its genome, the latter preventing breeders from taking advantage of the recent explosion of whole-genome sequencing that has benefited many other crops. Thus, modern sugarcane hybrids are the last remaining major crop without a reference-quality genome. Here we take a major step towards advancing sugarcane biotechnology by generating a polyploid reference genome for R570, a typical modern cultivar derived from interspecific hybridization between the domesticated species (Saccharum officinarum) and the wild species (Saccharum spontaneum). In contrast to the existing single haplotype ('monoploid') representation of R570, our 8.7 billion base assembly contains a complete representation of unique DNA sequences across the approximately 12 chromosome copies in this polyploid genome. Using this highly contiguous genome assembly, we filled a previously unsized gap within an R570 physical genetic map to describe the likely causal genes underlying the single-copy Bru1 brown rust resistance locus. This polyploid genome assembly with fine-grain descriptions of genome architecture and molecular targets for biotechnology will help accelerate molecular and transgenic breeding and adaptation of sugarcane to future environmental conditions.
Assuntos
Genoma de Planta , Poliploidia , Saccharum , Cromossomos de Plantas/genética , Genoma de Planta/genética , Haplótipos/genética , Hibridização Genética/genética , Melhoramento Vegetal , Saccharum/classificação , Saccharum/genética , Biotecnologia , Padrões de Referência , DNA de Plantas/genéticaRESUMO
There is a common perception that high body mass index (BMI) is associated with an increased risk of bleeding complications at the site of femoral puncture when manual compression is used for achieving hemostasis. Because of lack of evidence to support or refute this, we conducted a study to assess whether raised BMI is associated with increased risk of groin complications. 15 cases of groin complications after manual compression over 2 years and 40 controls were each divided into 3 groups according to BMI. Baseline characteristics of cases and controls were similar. High BMI was not found to be associated with increased risk of groin complications, suggesting that manual compression is safe and effective in patients with raised BMI.