This study reports the sequencing and analysis of the bread wheat genome, a globally important crop that accounts for 20% of human calorie intake. The researchers used 454 pyrosequencing to sequence the large, hexaploid wheat genome, which is 17 gigabases in size. They identified between 94,000 and 96,000 genes and assigned two-thirds of them to the three component genomes (A, B, and D). High-resolution synteny maps revealed many small disruptions in conserved gene order. The study found that the hexaploid genome is highly dynamic, with significant loss of gene family members during polyploidization and domestication, and an abundance of gene fragments. Several gene families involved in energy harvesting, metabolism, and growth were expanded, potentially contributing to crop productivity. The identification of extensive genetic variation provides a resource for accelerating gene discovery and improving wheat production. The authors also developed a genome-wide catalogue of single nucleotide polymorphisms (SNPs) in the A, B, and D genomes, which will facilitate genetic and genomic analysis of this key crop.This study reports the sequencing and analysis of the bread wheat genome, a globally important crop that accounts for 20% of human calorie intake. The researchers used 454 pyrosequencing to sequence the large, hexaploid wheat genome, which is 17 gigabases in size. They identified between 94,000 and 96,000 genes and assigned two-thirds of them to the three component genomes (A, B, and D). High-resolution synteny maps revealed many small disruptions in conserved gene order. The study found that the hexaploid genome is highly dynamic, with significant loss of gene family members during polyploidization and domestication, and an abundance of gene fragments. Several gene families involved in energy harvesting, metabolism, and growth were expanded, potentially contributing to crop productivity. The identification of extensive genetic variation provides a resource for accelerating gene discovery and improving wheat production. The authors also developed a genome-wide catalogue of single nucleotide polymorphisms (SNPs) in the A, B, and D genomes, which will facilitate genetic and genomic analysis of this key crop.