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The genome of the sea urchin Strongylocentrotus purpuratus

We report the sequence and analysis of the 814-megabase genome of the sea urchin Strongylocentrotus purpuratus, a model for developmental and systems biology. The sequencing strategy combined whole-genome shotgun and bacterial artificial chromosome (BAC) sequences. This use of BAC clones, aided by a pooling strategy, overcame difficulties associated with high heterozygosity of the genome. The geno

The genome of the model beetle and pest Tribolium castaneum

Tribolium castaneum is a member of the most species-rich eukaryotic order, a powerful model organism for the study of generalized insect development, and an important pest of stored agricultural products. We describe its genome sequence here. This omnivorous beetle has evolved the ability to interact with a diverse chemical environment, as shown by large expansions in odorant and gustatory recepto

Social insect genomes exhibit dramatic evolution in gene composition and regulation while preserving regulatory features linked to sociality

Genomes of eusocial insects code for dramatic examples of phenotypic plasticity and social organization. We compared the genomes of seven ants, the honeybee, and various solitary insects to examine whether eusocial lineages share distinct features of genomic organization. Each ant lineage contains ∼4000 novel genes, but only 64 of these genes are conserved among all seven ants. Many gene families

The GenoChip : a new tool for genetic anthropology

The Genographic Project is an international effort aimed at charting human migratory history. The project is nonprofit and nonmedical, and, through its Legacy Fund, supports locally led efforts to preserve indigenous and traditional cultures. Although the first phase of the project was focused on uniparentally inherited markers on the Y-chromosome and mitochondrial DNA (mtDNA), the current phase f

Cross-species analysis of genic GC3 content and DNA methylation patterns

The GC content in the third codon position (GC(3)) exhibits a unimodal distribution in many plant and animal genomes. Interestingly, grasses and homeotherm vertebrates exhibit a unique bimodal distribution. High GC(3) was previously found to be associated with variable expression, higher frequency of upstream TATA boxes, and an increase of GC(3) from 5' to 3'. Moreover, GC(3)-rich genes are predom

Gene expression and nucleotide composition are associated with genic methylation level in Oryza sativa

BACKGROUND: The methylation of cytosines at CpG dinucleotides, which plays an important role in gene expression regulation, is one of the most studied epigenetic modifications. Thus far, the detection of DNA methylation has been determined mostly by experimental methods, which are not only prone to bench effects and artifacts but are also time-consuming, expensive, and cannot be easily scaled up t

The 'extremely ancient' chromosome that isn't : a forensic bioinformatic investigation of Albert Perry's X-degenerate portion of the Y chromosome

Mendez and colleagues reported the identification of a Y chromosome haplotype (the A00 lineage) that lies at the basal position of the Y chromosome phylogenetic tree. Incorporating this haplotype, the authors estimated the time to the most recent common ancestor (TMRCA) for the Y tree to be 338,000 years ago (95% CI=237,000-581,000). Such an extraordinarily early estimate contradicts all previous

A comparative study and a phylogenetic exploration of the compositional architectures of mammalian nuclear genomes

For the past four decades the compositional organization of the mammalian genome posed a formidable challenge to molecular evolutionists attempting to explain it from an evolutionary perspective. Unfortunately, most of the explanations adhered to the "isochore theory," which has long been rebutted. Recently, an alternative compositional domain model was proposed depicting the human and cow genomes

Finding the missing honey bee genes : lessons learned from a genome upgrade

BACKGROUND: The first generation of genome sequence assemblies and annotations have had a significant impact upon our understanding of the biology of the sequenced species, the phylogenetic relationships among species, the study of populations within and across species, and have informed the biology of humans. As only a few Metazoan genomes are approaching finished quality (human, mouse, fly and w

On the immortality of television sets : "function" in the human genome according to the evolution-free gospel of ENCODE

A recent slew of ENCyclopedia Of DNA Elements (ENCODE) Consortium publications, specifically the article signed by all Consortium members, put forward the idea that more than 80% of the human genome is functional. This claim flies in the face of current estimates according to which the fraction of the genome that is evolutionarily conserved through purifying selection is less than 10%. Thus, accor

The "inverse relationship between evolutionary rate and age of mammalian genes" is an artifact of increased genetic distance with rate of evolution and time of divergence

It has recently been claimed that older genes tend to evolve more slowly than newer ones (Alba and Castresana 2005). By simulation of genes of equal age, we show that the inverse correlation between age and rate is an artifact caused by our inability to detect homology when evolutionary distances are large. Since evolutionary distance increases with time of divergence and rate of evolution, homolo

Genomics and epidemiology for gastric adenocarcinomas (GE4GAC): a Brazilian initiative to study gastric cancer

Gastric cancer (GC) is the fifth most common type of cancer worldwide with high incidences in Asia, Central, and South American countries. This patchy distribution means that GC studies are neglected by large research centers from developed countries. The need for further understanding of this complex disease, including the local importance of epidemiological factors and the rich ancestral admixtu