Search

A new DNA analysis method termed long fragment read technology is described, and the approach is used to determine parental haplotypes and to sequence human genomes cost-effectively and accurately from only 10 to 20 cells.

Whole-exome analysis of individuals with developmental disorders shows that de novo mutations can equally cause loss or altered protein function, but that most mutations causing altered protein function have not yet been described.

The authors analyzed the whole-exome sequences of over 16,000 individuals and found that very rare variants predicted to disrupt the SETD1A gene confer substantial risk for schizophrenia. Damaging variants in SETD1A were also associated with diverse, severe developmental disorders, providing an important genetic link between schizophrenia and other neurodevelopmental disorders.

A study of several longitudinal birth cohorts and cross-sectional cohorts finds only moderate overlap in genetic variants between autism that is diagnosed earlier and that diagnosed later, so they may represent aetiologically different conditions.

Matthew Hurles and colleagues report the first direct comparative analysis of male and female germline mutation rates from whole-genome sequences of two parent-offspring trios sequenced as part of the 1000 Genomes Project. They identify variation in paternal and maternal mutation rates between these two families.

Low read depth sequencing of whole genomes and high read depth exomes of nearly 10,000 extensively phenotyped individuals are combined to help characterize novel sequence variants, generate a highly accurate imputation reference panel and identify novel alleles associated with lipid-related traits; in addition to describing population structure and providing functional annotation of rare and low-frequency variants the authors use the data to estimate the benefits of sequencing for association studies.

Andrew Jackson, Grant Stewart, Bernd Wollnik and colleagues identify TRAIP mutations in three patients with primordial dwarfism. They show that TRAIP is involved in DNA damage response during genome replication and is necessary for efficient cell cycle progression.

Whole-genome sequencing analysis of individuals with primary immunodeficiency identifies new candidate disease-associated genes and shows how the interplay between genetic variants can explain the variable penetrance and complexity of the disease.

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.

This report from the 1000 Genomes Project describes the genomes of 1,092 individuals from 14 human populations, providing a resource for common and low-frequency variant analysis in individuals from diverse populations; hundreds of rare non-coding variants at conserved sites, such as motif-disrupting changes in transcription-factor-binding sites, can be found in each individual.

The goal of the 1000 Genomes Project is to provide in-depth information on variation in human genome sequences. In the pilot phase reported here, different strategies for genome-wide sequencing, using high-throughput sequencing platforms, were developed and compared. The resulting data set includes more than 95% of the currently accessible variants found in any individual, and can be used to inform association and functional studies.

By integrating healthcare and exome-sequencing data from parent–offspring trios of patients with developmental disorders, 28 genes that had not previously been associated with developmental disorders were identified.

Patients with neurodevelopmental conditions without a monogenic diagnosis have a higher polygenic burden than those with a monogenic diagnosis. Non-transmitted common alleles in the parents are associated with the child’s phenotype, and the common and rare variants conferring risk are correlated.

Results for the final phase of the 1000 Genomes Project are presented including whole-genome sequencing, targeted exome sequencing, and genotyping on high-density SNP arrays for 2,504 individuals across 26 populations, providing a global reference data set to support biomedical genetics.

Developmental disorders (DDs) are more prevalent in males, thought to be due to X-linked genetic variation. Here, the authors investigate the burden of X-linked coding variants in 11,044 DD patients, showing that this contributes to ~6% of both male and female cases and therefore does not solely explain male bias in DDs.

The non-coding RNA RNU4-2, which is highly expressed in the developing human brain, is identified as a syndromic neurodevelopmental disorder gene, and, using RNA sequencing, 5′ splice-site use is shown to be systematically disrupted in individuals with RNU4-2 variants.

Analysis of autosomal recessive coding variants in 29,745 trios from the DDD study and GeneDx provides insights into the genetic architecture of developmental disorders across ancestrally diverse populations.

Whole-exome sequencing has revolutionized the identification of genes with dominant disease-associated variants for rare clinically and genetically heterogeneous disorders, but the identification of genes with recessive disease-associated variants has been less successful. A new study now provides a framework integrating Mendelian variant filtering with statistical assessments of patients' genotypes and phenotypes, thereby catalyzing the discovery of novel mutations associated with recessive disease.

Constantinides et al., perform a recall study from a British South Asian genetic cohort to explore the genetic and phenotypic risk of cholestatic liver disease. 55.6% of participants with rare heterozygous ABCB4/ABCB11 variants or a history of intrahepatic cholestasis of pregnancy showed evidence of liver involvement, highlighting the utility of genetic screening and monitoring.

A global network of researchers was formed to investigate the role of human genetics in SARS-CoV-2 infection and COVID-19 severity; this paper reports 13 genome-wide significant loci and potentially actionable mechanisms in response to infection.

Here, the authors used electronic healthcare records to analyse the genetic basis of variation in 42 routinely-acquired quantitative blood tests among up to 40,000 British South Asian volunteers from the Genes and Health study. By combining their results with genetic findings from UK Biobank, they explore similarities and differences between ancestries in the genetic basis of these traits.

Comprehensive factor analysis of core diagnostic features provides insights into the complex genetic architecture underlying phenotypic heterogeneity in autism.

Harnessing information from whole genome sequencing in 185 individuals, this study generates a high-resolution map of copy number variants. Nucleotide resolution of the map facilitates analysis of structural variant distribution and identification of the mechanisms of their origin. The study provides a resource for sequence-based association studies.

Here the authors present a human pluripotent stem cell-derived three-dimensional organoid culture system that is able to recapitulate several aspects of human brain development in addition to modelling the brain disorder microcephaly, which has been difficult to achieve using mouse models.

Diagnostic filtering is an important step to analyze the functional and clinical significance of the large number of genetic variants identified from next-generation genome sequencing data. Here, the authors develop a flexible and scalable system for diagnostic filtering of genetic variants using G2P with Ensembl VEP.

Investigation of variation in three cohorts has identified multiple genetic signals associated with the pregnancy-specific liver disorder, intrahepatic cholestasis of pregnancy, giving insight into the disease which can cause preterm birth and stillbirth.

Estimates of human mutation rates differ substantially based on the approach. Here, the authors present a multi-generational estimate from the autozygous segment in a non-European population that gives insight into the contribution of post-zygotic mutations and population-specific mutational processes.

In a cohort of 50,556 South Asian individuals, partitioned polygenic scores helped identify genetic susceptibility to insulin deficiency and unfavorable fat distribution as key drivers of young-onset T2D diagnosis and faster progression to diabetes-related complications.

Whole-genome sequencing and phenotype data sharing are introduced in a national health system to streamline diagnosis and to discover coding and non-coding variants that cause rare diseases.

Systematic analysis of postzygotic mosaicism (PZM) is difficult due to challenges in detecting such events. Here, Wright et al. analyse trio exome sequencing data from blood and saliva of 4,293 probands with developmental disorders from the DDD Study and estimate that >3% of causative de novo mutations result from PZM.

Copy number variants (CNVs) account for a major proportion of human genetic diversity and may contribute to genetic susceptibility to disease. Here, a large, genome-wide study of association between common CNVs and eight common human diseases is presented. The study provides a wealth of technical insights that will inform future study design and analysis. The results also indicate that common CNVs that can be 'typed' on existing platforms are unlikely to contribute much to the genetic basis of common diseases.

1000 Genomes imputation can increase the power of genome-wide association studies to detect genetic variants associated with human traits and diseases. Here, the authors develop a method to integrate and analyse low-coverage sequence data and SNP array data, and show that it improves imputation performance.

Levels of circulating thyrotropin and free thyroxine reflect thyroid function, however, their genetic underpinnings remain poorly understood. Taylor et al. take advantage of whole-genome sequence data from cohorts within the UK10K project to identify novel variants associated with these traits.

Population-based genome sequencing provides an increasingly rich resource for the identification of low-frequency, large effect variants associated with clinically important phenotypes. Timpson et al. use UK10K data to identify a variant of the APOC3gene strongly associated with plasma triglyceride levels.

The authors report the mutational landscape of 29 cell types from microdissected biopsies from 19 organs and explore the mechanisms underlying mutation rates in normal tissues.

Recent evidence has questioned the dogma of strict maternal transmission of mitochondrial DNA (mtDNA) in humans. Wei et al. saw no evidence of paternal transmission of mtDNA in 11,035 human trios, and show that nuclear-mitochondrial segments (NUMTs) can give the impression of paternal mtDNA transmission, but are actually inherited through the nuclear genome.

The Structural Variation Analysis Group of The 1000 Genomes Project reports an integrated structural variation map based on discovery and genotyping of eight major structural variation classes in 2,504 unrelated individuals from across 26 populations; structural variation is compared within and between populations and its functional impact is quantified.

Gene conversion — the unidirectional transfer of information between highly homologous sequences — influences genome evolution and is the cause of several human inherited disorders. This article reviews our understanding of the mechanism of gene conversion, and its consequences for human health.

Chromodomain Helicase DNA-binding (CHD) proteins have been implicated in neurodevelopmental processes. Here, the authors identify missense variants in CHD3 that disturb its chromatin remodeling activities and cause a neurodevelopmental disorder with macrocephaly and speech and language impairment.

Severe congenital development defects such as Jeune syndrome can result from the malfunction of primary cilia and dynein. Here Schmidts et al. report unique biallelic null mutations in a gene encoding a dynein light chain, helping to explain the nature of ciliopathies in human patients.