Research articles

Kjetill S. Jakobsen, Sissel Jentoft and colleagues assemble partial draft genomes and analyze sequences from 66 teleost fish species to determine major histocompatibility complex (MHC) class I and class II gene status. They find that MHC II is absent from the Gadiformes lineage, while MHC I gene expansions have occurred multiple times.

Ken-ichi Noma and colleagues use ChIA-PET to identify genome-wide associations mediated by condensin and cohesin in fission yeast. They find that cohesin and condensin generate small and larger chromatin domains, respectively, and that condensin, but not cohesin, connects cell cycle–regulated genes bound by mitotic transcription factors.

Murat Günel and colleagues identify recurrent mutations in POLR2A, which encodes the catalytic subunit of RNA polymerase II, in a subset of meningiomas. They find that POLR2A-mutant tumors can be distinguished on the basis of their super-enhancer and gene expression profiles, which show dysregulation of key meningeal identity genes.

Nicholas Feasey and colleagues report whole-genome sequence analysis of 675 isolates of Salmonella enterica serovar Enteritidis from 45 countries. They find evidence for a global epidemic clade associated with enterocolitis and two novel clades restricted to distinct regions of Africa and associated with invasive disease.

Douglas Ruderfer, Shaun Purcell and colleagues characterized the rates and properties of rare genic copy number variants in exome sequencing data from nearly 60,000 individuals in the Exome Aggregation Consortium. These data are available through an integrated database that spans the spectrum of human genetic variation, aiding in the interpretation of personal genomes and population-based disease studies.

Housheng Hansen He and colleagues perform an integrated analysis and identify 45 candidate long noncoding RNAs (lncRNAs) associated with prostate cancer risk. They further show that a prostate cancer risk allele in the 8q24 region results in upregulation of the lncRNA PCAT1, which promotes prostate cancer cell proliferation and tumor growth.

Nicholas Navin and colleagues use highly multiplexed single-nucleus sequencing to investigate DNA copy number evolution in patients with triple-negative breast cancer. Their data suggest that most copy number alterations are acquired at the earliest stages of tumor evolution in short punctuated bursts, followed by stable clonal expansions that form the tumor mass.

Xiaowu Wang, Jian Wu, Guusje Bonnema and colleagues report resequencing and subgenome selection analysis of 199 Brassica rapa and 119 Brassica oleracea accessions representing diverse morphotypes. They identify 4 subgenome loci with evidence of parallel selection among subgenomes and 15 subgenome loci with evidence of parallel selection between species.

Feng Qin and colleagues perform a genome-wide association study for drought tolerance in maize seedlings and find 42 candidate genes. They characterize a promoter insertion in the ZmVPP1 gene containing MYB-binding sites, which enables the drought-inducible expression of ZmVPP1, leading to drought tolerance, a phenotype confirmed through transgenic experiments.

Howard Chang, Ravindra Majeti and colleagues define the chromatin accessibility and transcriptional landscapes in 13 human primary blood cell types and in acute myeloid leukemia cells. They identify potential regulators governing hematopoietic differentiation and genetic elements linked to regulatory evolution in cancer cells.

Rachel Meyer and colleagues use whole-genome resequencing of 93 African rice landraces to generate a SNP map used for population analysis and a genome-wide association study for salt tolerance traits. They find 11 significant loci, some with signatures of positive selection, and evidence for a population bottleneck beginning around 15,000 years ago.

Yongfeng Shang and colleagues report that the pioneering factor FOXA1 associates with DNA repair complexes and regulates DNA demethylation at its genomic targets in a DNA polymerase β–dependent manner. They show that FOXA1-associated DNA demethylation is coupled with genomic targeting of estrogen receptor α and estrogen responsiveness in a breast cancer cell line.

Ewan Pearson, Kathleen Giacomini and the Metformin Genetics Consortium perform a genome-wide association study for glycemic response to the antidiabetic drug metformin. They find an intronic allele of the GLUT2 glucose transporter gene that associates with greater metformin action, an effect that is more pronounced in obese individuals.

Matthew Hurles and colleagues report exome sequencing of 1,891 individuals with syndromic or nonsyndromic congenital heart defects (CHD). They found that nonsyndromic CHD patients were enriched for protein-truncating variants in CHD-associated genes inherited from unaffected parents and identified three new syndromic CHD disorders caused by de novo mutations.

Victoria Hore, Jonathan Marchini and colleagues present a method for multiple-tissue gene expression studies aimed at uncovering gene networks linked to genetic variation. They apply their method to RNA sequencing data from adipose, skin and lymphoblastoid cell lines and identify several biologically relevant gene networks with a genetic basis.

Ashley Winslow, Roy Perlis, David Hinds and colleagues report the identification of 15 genetic loci associated with risk of major depressive disorder in individuals of European descent. They find that several loci are also associated with risk of other psychiatric traits, including schizophrenia and neuroticism.

Jonathan Pritchard, Christopher Garcia and colleagues examine associations between different T cell receptor V genes and MHC alleles by eQTL mapping. They find that there are strong associations between MHC variation and T cell receptor gene usage and map these signals to specific MHC amino acids, many of which physically interact with germline-encoded amino acids on the T cell receptor.

Yun Chen, Albin Sandelin, Torben Heick Jensen and colleagues describe general rules governing the expression of reverse-oriented promoter upstream transcripts (PROMPTs) based on the orientation and proximity of promoter pairs. They characterize how the distance between promoters affects the expression of PROMPTs and the usage of alternate mRNA transcription start sites.

Stephen McGarvey and colleagues identify a missense variant in CREBRF strongly associated with body mass index in Samoans. This variant is rare in other populations but is common in Samoans and has a much larger effect size than other known common obesity risk variants, including variation in FTO.

Ammar Al-Chalabi, Jan Veldink and colleagues perform a genome-wide association study for amyotrophic lateral sclerosis (ALS) in 15,156 cases and 26,242 controls. They identify three new genome-wide-significant variants and establish ALS as a complex trait with a polygenic architecture, but with a distinct and important role for low-frequency variants.