On the Genetic and Genomic Basis of Aggression, Violence, and Antisocial Behavior

There is a great deal of interest in examining the genetic and environmental architecture to aggression, violence, and antisocial behaviors. This interest has resulted in hundreds of studies being published that estimate genetic and environmental effects on antisocial phenotypes. The results generated from these studies have been remarkably consistent and have contributed greatly to the knowledge base on the etiology of antisocial behavior. This chapter reviews the research on the genetic basis to antisocial phenotypes by presenting the results related to the heritability of antisocial phenotypes. It also discusses some of the molecular genetic association studies as well as genome-wide association studies that focus on the development of antisocial behaviors. In doing so, it also reviews findings related to gene–environment interactions. The chapter concludes by discussing some of the ways in which these findings could be used for intervention and prevention programs.

Download Full-text

Genetics of PTSD

10.1093/med/9780190215422.003.0011 ◽

2016 ◽

Author(s):

Jennifer A. Sumner ◽

Angela C. Bustamante ◽

Karestan C. Koenen ◽

Monica Uddin

Keyword(s):

Association Studies ◽

Molecular Genetic ◽

Critical Role ◽

Trauma Exposure ◽

Genome Wide Association Studies ◽

Risk And Resilience ◽

New Developments ◽

Gene Environment ◽

Genome Wide

Trauma exposure and PTSD are heritable. However, the mechanisms of risk and resilience following trauma exposure are not yet well understood, suggesting that investigations into the genetic architecture of PTSD have much to contribute. This chapter reviews the rapidly growing literature on molecular genetic risk factors for PTSD, including findings from candidate gene and genome-wide association studies. Given the critical role of trauma exposure in the onset of PTSD, it also discusses gene-environment interplay, and highlights some recent findings from epigenetic studies. The chapter concludes by summarizing considerations for the field as it continues to move forward, and discusses exciting new developments in the search for genetic markers for PTSD.

Download Full-text

The Genetic Basis of Hypertriglyceridemia

Current Atherosclerosis Reports ◽

10.1007/s11883-021-00939-y ◽

2021 ◽

Vol 23 (8) ◽

Author(s):

Germán D. Carrasquilla ◽

Malene Revsbech Christiansen ◽

Tuomas O. Kilpeläinen

Keyword(s):

Genetic Basis ◽

Association Studies ◽

Cumulative Effect ◽

Genome Wide Association Studies ◽

Genetic Loci ◽

Risk Variants ◽

Genome Wide ◽

Severe Hypertriglyceridemia ◽

Increased Risk ◽

Polygenic Scores

Abstract Purpose of Review Hypertriglyceridemia is a common dyslipidemia associated with an increased risk of cardiovascular disease and pancreatitis. Severe hypertriglyceridemia may sometimes be a monogenic condition. However, in the vast majority of patients, hypertriglyceridemia is due to the cumulative effect of multiple genetic risk variants along with lifestyle factors, medications, and disease conditions that elevate triglyceride levels. In this review, we will summarize recent progress in the understanding of the genetic basis of hypertriglyceridemia. Recent Findings More than 300 genetic loci have been identified for association with triglyceride levels in large genome-wide association studies. Studies combining the loci into polygenic scores have demonstrated that some hypertriglyceridemia phenotypes previously attributed to monogenic inheritance have a polygenic basis. The new genetic discoveries have opened avenues for the development of more effective triglyceride-lowering treatments and raised interest towards genetic screening and tailored treatments against hypertriglyceridemia. Summary The discovery of multiple genetic loci associated with elevated triglyceride levels has led to improved understanding of the genetic basis of hypertriglyceridemia and opened new translational opportunities.

Download Full-text

Genomic basis of striking fin shapes and colours in the fighting fish

Molecular Biology and Evolution ◽

10.1093/molbev/msab110 ◽

2021 ◽

Author(s):

Le Wang ◽

Fei Sun ◽

Zi Yi Wan ◽

Baoqing Ye ◽

Yanfei Wen ◽

...

Keyword(s):

Evolutionary Biology ◽

Association Studies ◽

Regulatory Element ◽

Regulatory Elements ◽

Major Effect ◽

Betta Splendens ◽

Genome Wide Association Studies ◽

Genome Wide ◽

Phenotypic Variations ◽

Genomic Basis

Abstract Resolving the genomic basis underlying phenotypic variations is a question of great importance in evolutionary biology. However, understanding how genotypes determine the phenotypes is still challenging. Centuries of artificial selective breeding for beauty and aggression resulted in a plethora of colors, long fin varieties, and hyper-aggressive behavior in the air-breathing Siamese fighting fish (Betta splendens), supplying an excellent system for studying the genomic basis of phenotypic variations. Combining whole genome sequencing, QTL mapping, genome-wide association studies and genome editing, we investigated the genomic basis of huge morphological variation in fins and striking differences in coloration in the fighting fish. Results revealed that the double tail, elephant ear, albino and fin spot mutants each were determined by single major-effect loci. The elephant ear phenotype was likely related to differential expression of a potassium ion channel gene, kcnh8. The albinotic phenotype was likely linked to a cis-regulatory element acting on the mitfa gene and the double tail mutant was suggested to be caused by a deletion in a zic1/zic4 co-enhancer. Our data highlight that major loci and cis-regulatory elements play important roles in bringing about phenotypic innovations and establish Bettas as new powerful model to study the genomic basis of evolved changes.

Download Full-text

Insights into Dyslexia Genetics Research from the Last Two Decades

Brain Sciences ◽

10.3390/brainsci12010027 ◽

2021 ◽

Vol 12 (1) ◽

pp. 27

Author(s):

Florina Erbeli ◽

Marianne Rice ◽

Silvia Paracchini

Keyword(s):

Language Disorder ◽

Association Studies ◽

Neurodevelopmental Disorder ◽

Molecular Genetic ◽

Genetic Research ◽

Twin Studies ◽

Genome Wide Association Studies ◽

Genetics Research ◽

Genome Wide ◽

Genetic Risks

Dyslexia, a specific reading disability, is a common (up to 10% of children) and highly heritable (~70%) neurodevelopmental disorder. Behavioral and molecular genetic approaches are aimed towards dissecting its significant genetic component. In the proposed review, we will summarize advances in twin and molecular genetic research from the past 20 years. First, we will briefly outline the clinical and educational presentation and epidemiology of dyslexia. Next, we will summarize results from twin studies, followed by molecular genetic research (e.g., genome-wide association studies (GWASs)). In particular, we will highlight converging key insights from genetic research. (1) Dyslexia is a highly polygenic neurodevelopmental disorder with a complex genetic architecture. (2) Dyslexia categories share a large proportion of genetics with continuously distributed measures of reading skills, with shared genetic risks also seen across development. (3) Dyslexia genetic risks are shared with those implicated in many other neurodevelopmental disorders (e.g., developmental language disorder and dyscalculia). Finally, we will discuss the implications and future directions. As the diversity of genetic studies continues to increase through international collaborate efforts, we will highlight the challenges in advances of genetics discoveries in this field.

Download Full-text

GWAS of three molecular traits highlights core genes and pathways alongside a highly polygenic background

10.1101/2020.04.20.051631 ◽

2020 ◽

Cited By ~ 6

Author(s):

Nasa Sinnott-Armstrong ◽

Sahin Naqvi ◽

Manuel Rivas ◽

Jonathan K Pritchard

Keyword(s):

Complex Traits ◽

Genetic Basis ◽

Association Studies ◽

Genome Wide Association ◽

Genome Wide Association Studies ◽

Biological Processes ◽

Uk Biobank ◽

The Core ◽

Genome Wide ◽

Core Genes

SummaryGenome-wide association studies (GWAS) have been used to study the genetic basis of a wide variety of complex diseases and other traits. However, for most traits it remains difficult to interpret what genes and biological processes are impacted by the top hits. Here, as a contrast, we describe UK Biobank GWAS results for three molecular traits—urate, IGF-1, and testosterone—that are biologically simpler than most diseases, and for which we know a great deal in advance about the core genes and pathways. Unlike most GWAS of complex traits, for all three traits we find that most top hits are readily interpretable. We observe huge enrichment of significant signals near genes involved in the relevant biosynthesis, transport, or signaling pathways. We show how GWAS data illuminate the biology of variation in each trait, including insights into differences in testosterone regulation between females and males. Meanwhile, in other respects the results are reminiscent of GWAS for more-complex traits. In particular, even these molecular traits are highly polygenic, with most of the variance coming not from core genes, but from thousands to tens of thousands of variants spread across most of the genome. Given that diseases are often impacted by many distinct biological processes, including these three, our results help to illustrate why so many variants can affect risk for any given disease.

Download Full-text

A deletion in GDF7 is associated with a heritable forebrain commissural malformation concurrent with ventriculomegaly and interhemispheric cysts in cats

10.1101/2020.05.12.091686 ◽

2020 ◽

Cited By ~ 1

Author(s):

Yoshihiko Yu ◽

Erica K. Creighton ◽

Reuben M. Buckley ◽

Leslie A. Lyons ◽

Keyword(s):

Genetic Basis ◽

Association Studies ◽

Homozygosity Mapping ◽

Mammalian Brain ◽

Genome Wide Association Studies ◽

Commissural Axons ◽

Genome Wide ◽

Mixed Breed ◽

Roof Plate ◽

Control Association

AbstractAn inherited neurologic syndrome in a family of mixed-breed Oriental cats has been characterized as forebrain commissural malformation concurrent with ventriculomegaly and interhemispheric cysts. However, the genetic basis for this autosomal recessive syndrome in cats is unknown. Forty-three cats were genotyped on the Illumina Infinium Feline 63K iSelect DNA Array and used for analyses. Genome-wide association studies, including a sib-transmission disequilibrium test, a case-control association analysis, and homozygosity mapping, identified a critical region on cat chromosome A3. Short-read whole genome sequencing was completed for a cat trio segregating with the syndrome. A homozygous 7 bp deletion in growth differentiation factor 7 (GDF7) (c.221_227delGCCGCGC [p.Arg74Profs]) was identified in affected cats by comparison to the 99 Lives Cat variant dataset, validated using Sanger sequencing, and genotyped by fragment analyses. This variant was not identified in 192 unaffected cats in the 99 Lives dataset. The variant segregated concordantly in an extended pedigree. Obligate carrier cats were heterozygous. In mice, GDF7 mRNA is expressed within the roof plate when commissural axons initiate ventrally-directed growth. This finding emphasizes the importance of GDF7 in the neurodevelopmental process in the mammalian brain. A genetic test can be developed for use by cat breeders to eradicate this variant.

Download Full-text

Current Challenges in the Genetics of Psoriatic Arthritis: A Report from the GRAPPA 2009 Annual Meeting

The Journal of Rheumatology ◽

10.3899/jrheum.101123 ◽

2011 ◽

Vol 38 (3) ◽

pp. 564-566 ◽

Cited By ~ 2

Author(s):

PROTON RAHMAN

Keyword(s):

Psoriatic Arthritis ◽

Annual Meeting ◽

Association Studies ◽

Environment Interaction ◽

Genome Wide Association Studies ◽

Novel Genes ◽

Gene Environment Interaction ◽

Gene Environment ◽

Genome Wide

Psoriasis and psoriatic arthritis (PsA) are heterogeneous diseases. While both have a strong genetic basis, it is strongest for PsA, where fewer investigators are studying its genetics. Over the last year the number of independent genetic loci associated with psoriasis has substantially increased, mostly due to completion of multiple genome-wide association studies (GWAS) in psoriasis. At least 2 GWAS efforts are now under way in PsA to identify novel genes in this disease; a metaanalysis of genome-wide scans and further studies must follow to examine the genetics of disease expression, epistatic interaction, and gene-environment interaction. In the long term, it is anticipated that genome-wide sequencing is likely to generate another wave of novel genes in PsA. At the annual meeting of the Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA) in Stockholm, Sweden, in 2009, members discussed issues and challenges regarding the advancement of the genetics of PsA; results of those discussions are summarized here.

Download Full-text

Genetic Methodologies and Applications

10.1093/med/9780190681425.003.0001 ◽

2017 ◽

Author(s):

Shaun M. Purcell

Keyword(s):

Mental Illness ◽

Genetic Risk ◽

Genetic Basis ◽

Common Mental Disorders ◽

Association Studies ◽

Genome Wide Association Studies ◽

The Past ◽

Genome Wide ◽

Experimental Approaches ◽

Large Families

Mental illness is highly heritable, yet it has been difficult historically to identify the specific genes that comprise that risk. This difficulty resides in the fact that the genetic risk for all common mental disorders is polygenic, with perhaps hundreds of genetic variations, each of small effect, contributing to the overall risk. Despite these challenges, the field has made dramatic advances over the past decade in beginning to understand the genetic basis of mental illness. This chapter provides an overview of the experimental approaches used, beginning with epidemiology and population genetics to define the heritability of an illness, to classic studies of large families and linkage disequilibrium analysis, to genome-wide investigations including genome-wide association studies (GWAS), exome sequencing, and whole genome sequencing. Increasingly, these genetic advances are being understood within the biological context of disease pathophysiology.

Download Full-text

Genetic basis of intracranial aneurysm formation and rupture: clinical implications in the postgenomic era

Neurosurgical FOCUS ◽

10.3171/2019.4.focus19204 ◽

2019 ◽

Vol 47 (1) ◽

pp. E10 ◽

Cited By ~ 6

Author(s):

Nardin Samuel ◽

Ivan Radovanovic

Keyword(s):

Intracranial Aneurysm ◽

Genetic Basis ◽

Molecular Mechanisms ◽

Aneurysmal Subarachnoid Hemorrhage ◽

Association Studies ◽

Genome Wide Association Studies ◽

Genetic Aberrations ◽

Aneurysm Formation ◽

Genome Wide ◽

Risk Of Rupture

OBJECTIVEDespite the prevalence and impact of intracranial aneurysms (IAs), the molecular basis of their pathogenesis remains largely unknown. Moreover, there is a dearth of clinically validated biomarkers to efficiently screen patients with IAs and prognosticate risk for rupture. The aim of this study was to survey the literature to systematically identify the spectrum of genetic aberrations that have been identified in IA formation and risk of rupture.METHODSA literature search was performed using the Medical Subject Headings (MeSH) system of databases including PubMed, EMBASE, and Google Scholar. Relevant studies that reported on genetic analyses of IAs, rupture risk, and long-term outcomes were included in the qualitative analysis.RESULTSA total of 114 studies were reviewed and 65 were included in the qualitative synthesis. There are several well-established mendelian syndromes that confer risk to IAs, with variable frequency. Linkage analyses, genome-wide association studies, candidate gene studies, and exome sequencing identify several recurrent polymorphic variants at candidate loci, and genes associated with the risk of aneurysm formation and rupture, including ANRIL (CDKN2B-AS1, 9p21), ARGHEF17 (11q13), ELN (7q11), SERPINA3 (14q32), and SOX17 (8q11). In addition, polymorphisms in eNOS/NOS3 (7q36) may serve as predictive markers for outcomes following intracranial aneurysm rupture. Genetic aberrations identified to date converge on posited molecular mechanisms involved in vascular remodeling, with strong implications for an associated immune-mediated inflammatory response.CONCLUSIONSComprehensive studies of IA formation and rupture have identified candidate risk variants and loci; however, further genome-wide analyses are needed to identify high-confidence genetic aberrations. The literature supports a role for several risk loci in aneurysm formation and rupture with putative candidate genes. A thorough understanding of the genetic basis governing risk of IA development and the resultant aneurysmal subarachnoid hemorrhage may aid in screening, clinical management, and risk stratification of these patients, and it may also enable identification of putative mechanisms for future drug development.

Download Full-text

Genome-wide association studies of cardiac electrical phenotypes

Cardiovascular Research ◽

10.1093/cvr/cvaa144 ◽

2020 ◽

Vol 116 (9) ◽

pp. 1620-1634

Author(s):

Charlotte Glinge ◽

Najim Lahrouchi ◽

Reza Jabbari ◽

Jacob Tfelt-Hansen ◽

Connie R Bezzina

Keyword(s):

Genetic Basis ◽

Association Studies ◽

Individual Variability ◽

Genome Wide Association ◽

Genome Wide Association Studies ◽

Nucleotide Polymorphisms ◽

Genome Wide ◽

Challenges And Opportunities ◽

Electrocardiographic Parameters

Abstract The genetic basis of cardiac electrical phenotypes has in the last 25 years been the subject of intense investigation. While in the first years, such efforts were dominated by the study of familial arrhythmia syndromes, in recent years, large consortia of investigators have successfully pursued genome-wide association studies (GWAS) for the identification of single-nucleotide polymorphisms that govern inter-individual variability in electrocardiographic parameters in the general population. We here provide a review of GWAS conducted on cardiac electrical phenotypes in the last 14 years and discuss the implications of these discoveries for our understanding of the genetic basis of disease susceptibility and variability in disease severity. Furthermore, we review functional follow-up studies that have been conducted on GWAS loci associated with cardiac electrical phenotypes and highlight the challenges and opportunities offered by such studies.

Download Full-text