Nature Reviews Genetics 10, 740 (2009). doi:10.1038/nrg2691

Author: Tanita Casci

A study into the patterning of the fruitfly wing has led to a new model of how morphogen gradients confer positional information. It concludes that the response of cells to Hedgehog (HH) depends not so much on the local concentration of HH but on their

Nature Reviews Genetics 10, 739 (2009). doi:10.1038/nrg2692

Author: Mary Muers

The list of biological processes that are controlled by chromatin structure or small RNAs has expanded rapidly in recent years, and a few examples are emerging in which these two modes of regulation are connected. Research presented in three companion papers now links an RNAi

Nature Reviews Genetics 10, 740 (2009). doi:10.1038/nrg2686

Author: Magdalena Skipper

Both sequence-level and structural variation — including indels, copy number variants (CNVs) and inversions — contribute to genetic differences among individuals. Although sequence-level variation has been catalogued more extensively, structural variation, when considered per base pair, makes a greater contribution to overall variation. A comprehensive

Nature Reviews Genetics 10, 738 (2009). doi:10.1038/nrg2688

Author: Meera Swami

Gastrulation is a key process during early embryonic patterning in which a single epithelial layer develops into three germ layers — ectoderm, mesoderm and endoderm — and the axes of the embryo are formed. A recent study challenges the paradigm that the three germ layers

Nature Reviews Genetics 10, 738 (2009). doi:10.1038/nrg2690

Author: Christiaan van Ooij

Three new papers report a link between variants in the interleukin-28B (IL28B) gene and lack of response to treatment for hepatitis C virus (HCV) infection.About 3% of the world's population is infected with HCV, which is the leading cause of liver cirrhosis

Nature Reviews Genetics 10, 797 (2009). doi:10.1038/nrg2687

Authors: Thomas M. Williams & Sean B. Carroll

Sexual dimorphism is common throughout the animal kingdom. However, a molecular understanding of how sex-specific traits develop and evolve has been elusive. Recently, substantial progress has been made in elucidating how diverse sex-determination systems are integrated into developmental gene networks. One common theme from these

Nature Reviews Genetics 10, 743 (2009). doi:10.1038/nrg2684

Author: Donna Dickenson

Five years ago I published an article in this journal in which I predicted that we would soon witness an exploitative global market in human eggs for stem cell research. That prophecy came one step nearer on 11 June this year, when the New

Nature Reviews Genetics 10, 737 (2009). doi:10.1038/nrg2685

Author: Mary Muers

Crossovers between chromosomes are essential for correct chromosomal segregation during meiosis, and errors in crossover during recombination can result in aneuploidy, which has severe developmental consequences. Although the distribution and frequency of crossovers is known to be non-random — for example, recombination 'hot spots' are

Nature Reviews Genetics 10, 741 (2009). doi:10.1038/nrg2682

Author: Louisa Flintoft

The powerful genetic tools of Saccharomyces cerevisiae have so far been unavailable for the study of RNA interference (RNAi). Efforts to identify key components of the RNAi machinery in this species have proved futile, and the pathway has been assumed lost in all budding

Nature Reviews Genetics 10, 745 (2009). doi:10.1038/nrg2632

Authors: John Novembre & Anna Di Rienzo

Empowered by technology and sampling efforts designed to facilitate genome-wide association mapping, human geneticists are now studying the geography of genetic variation in unprecedented detail. With high genomic coverage and geographic resolution, these studies are identifying loci with spatial signatures of selection, such as extreme

Nature Reviews Genetics 10, 805 (2009). doi:10.1038/nrg2651

Authors: Peter A. Jones & Gangning Liang

DNA methylation patterns are set up early in mammalian development and are then copied during the division of somatic cells. A long-established model for the maintenance of these patterns explains some, but not all, of the data that are now available. We propose a new

Nature Reviews Genetics 10, 756 (2009). doi:10.1038/nrg2663

Authors: James E. Cleaver, Ernest T. Lam & Ingrid Revet

Mutations in genes on the nucleotide excision repair pathway are associated with diseases, such as xeroderma pigmentosum, Cockayne syndrome and trichothiodystrophy, that involve skin cancer and developmental and neurological symptoms. These mutations cause the defective repair of damaged DNA and increased transcription arrest but, except

Nature Reviews Genetics 10, 769 (2009). doi:10.1038/nrg2680

Authors: Patrick A. Dion, Hussein Daoud & Guy A. Rouleau

The past few years have seen the identification of dozens of genes with causal roles in motor neuron diseases (MNDs), particularly for amyotrophic lateral sclerosis and hereditary spastic paraplegia. Although many additional MND genes remain to be identified, the accumulated genetic evidence has already provided

Nature Reviews Genetics 10, 783 (2009). doi:10.1038/nrg2664

Authors: Deborah Charlesworth & John H. Willis

Inbreeding depression — the reduced survival and fertility of offspring of related individuals — occurs in wild animal and plant populations as well as in humans, indicating that genetic variation in fitness traits exists in natural populations. Inbreeding depression is important in the evolution of

Nature Reviews Genetics 10, 738 (2009). doi:10.1038/nrg2693

Epigenetics

Nature Reviews Genetics 10, 742 (2009). doi:10.1038/nrg2694

Genome Evolution

Nature Reviews Genetics 10, 735 (2009). doi:10.1038/nrg2696

The publicity surrounding the Darwin anniversaries this year has boosted interest in the principles of genetics, such as natural selection and fitness. Our article series on Fundamental Concepts in Genetics (http://www.nature.com/nrg/series/fundamental) has highlighted how these key ideas have developed and how they remain

Nature Reviews Genetics 10, 742 (2009). doi:10.1038/nrg2699

Author: Tanita Casci

Evolution marches relentlessly on and, it has now been found, it travels on a one-way street. By manipulating the evolutionary changes that have affected the function of the vertebrate glucocorticoid receptor, Thornton and colleagues have shown that ancestral states cannot be reached simply by reversing