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The Ensembl Variant Effect Predictor (VEP) is a freely available, open‐source tool for the annotation and filtering of genomic variants. It predicts variant molecular consequences using the Ensembl/GENCODE or RefSeq gene sets. It also reports phenotype associations from databases such as ClinVar, allele frequencies from studies including gnomAD, and predictions of deleteriousness from tools such as Sorting Intolerant From Tolerant and Combined Annotation Dependent Depletion. Ensembl VEP includes filtering options to customize variant prioritization. It is well supported and updated roughly quarterly to incorporate the latest gene, variant, and phenotype association information. Ensembl VEP analysis can be performed using a highly configurable, extensible command‐line tool, a Representational State Transfer application programming interface, and a user‐friendly web interface. These access methods are designed to suit different levels of bioinformatics experience and meet different needs in terms of data size, visualization, and flexibility. In this tutorial, we will describe performing variant annotation using the Ensembl VEP web tool, which enables sophisticated analysis through a simple interface. [ABSTRACT FROM AUTHOR]

A nonsense allele at rs1343879 in human MAGEE2 on chromosome X has previously been reported as a strong candidate for positive selection in East Asia. This premature stop codon causing ∼80% protein truncation is characterized by a striking geographical pattern of high population differentiation: common in Asia and the Americas (up to 84% in the 1000 Genomes Project East Asians) but rare elsewhere. Here, we generated a Magee2 mouse knockout mimicking the human loss-of-function mutation to study its functional consequences. The Magee2 null mice did not exhibit gross abnormalities apart from enlarged brain structures (13% increased total brain area, P  =   0.0022) in hemizygous males. The area of the granular retrosplenial cortex responsible for memory, navigation, and spatial information processing was the most severely affected, exhibiting an enlargement of 34% (P  =   3.4×10−6). The brain size in homozygous females showed the opposite trend of reduced brain size, although this did not reach statistical significance. With these insights, we performed human association analyses between brain size measurements and rs1343879 genotypes in 141 Chinese volunteers with brain MRI scans, replicating the sexual dimorphism seen in the knockout mouse model. The derived stop gain allele was significantly associated with a larger volume of gray matter in males (P  =   0.00094), and smaller volumes of gray (P  =   0.00021) and white (P  =   0.0015) matter in females. It is unclear whether or not the observed neuroanatomical phenotypes affect behavior or cognition, but it might have been the driving force underlying the positive selection in humans. [ABSTRACT FROM AUTHOR]

Classic selective sweeps occur when positive selection increases a variant's frequency from low to high in a population, and underlie some long‐studied human characteristics such as variation in skin, hair or eye colour. In such well‐studied 'gold standard' examples, a known variant has been associated with a plausible phenotype and underlying selective force. Signatures of classic sweeps have more recently been detected in population‐genetic data independently of any prior information about the corresponding phenotype or selective force, and usually without suggesting any insights into these. Motivated by the need to understand such candidates, we first review the gold standards and show that our understanding of them is often incomplete or unconvincing; only two of the examples we consider are compellingly explained. We assess approaches for large‐scale association of classic sweep candidate variants to phenotypes and selective forces, test these on the gold standards, and discuss the standards of evidence needed to adequately understand a selective sweep. [ABSTRACT FROM AUTHOR]

Genetic studies of type 1 diabetes (T1D) have identified 50 susceptibility regions1,2 (www.T1DBase.org) revealing major pathways contributing to risk3, with some loci shared across immune disorders4–6. In order to make genetic comparisons across autoimmune disorders as informative as possible a dense genotyping array, the ImmunoChip, was developed, from which four novel T1D regions were identified (P < 5 × 10−8). A comparative analysis with 15 immune diseases (www.ImmunoBase.org) revealed that T1D is more similar genetically to other autoantibody-positive diseases, most significantly to juvenile idiopathic arthritis and least to ulcerative colitis, and provided support for three additional novel T1D loci. Using a Bayesian approach, we defined credible sets for the T1D SNPs. These T1D SNPs localized to enhancer sequences active in thymus, T and B cells, and CD34+ stem cells. Enhancer-promoter interactions can now be analyzed in these cell types to identify which particular genes and regulatory sequences are causal.

The Canaanites inhabited the Levant region during the Bronze Age and established a culture that became influential in the Near East and beyond. However, the Canaanites, unlike most other ancient Near Easterners of this period, left few surviving textual records and thus their origin and relationship to ancient and present-day populations remain unclear. In this study, we sequenced five whole genomes from ∼3,700-year-old individuals from the city of Sidon, a major Canaanite city-state on the Eastern Mediterranean coast. We also sequenced the genomes of 99 individuals from present-day Lebanon to catalog modern Levantine genetic diversity. We find that a Bronze Age Canaanite-related ancestry was widespread in the region, shared among urban populations inhabiting the coast (Sidon) and inland populations (Jordan) who likely lived in farming societies or were pastoral nomads. This Canaanite-related ancestry derived from mixture between local Neolithic populations and eastern migrants genetically related to Chalcolithic Iranians. We estimate, using linkage-disequilibrium decay patterns, that admixture occurred 6,600–3,550 years ago, coinciding with recorded massive population movements in Mesopotamia during the mid-Holocene. We show that present-day Lebanese derive most of their ancestry from a Canaanite-related population, which therefore implies substantial genetic continuity in the Levant since at least the Bronze Age. In addition, we find Eurasian ancestry in the Lebanese not present in Bronze Age or earlier Levantines. We estimate that this Eurasian ancestry arrived in the Levant around 3,750–2,170 years ago during a period of successive conquests by distant populations. [ABSTRACT FROM AUTHOR]