Richard H Myers

Boston University | BU · Genome Science Institute

Huntington's disease (HD), due to expansion of a CAG repeat in HTT , is representative of a growing number of disorders involving somatically unstable short tandem repeats. We find that overlapping and distinct genetic modifiers of clinical landmarks and somatic expansion in blood DNA reveal an underlying complexity and cell-type specificity to the...

Objective: The aim of this study was to search for genes/variants that modify the effect of LRRK2 mutations in terms of penetrance and age-at-onset of Parkinson's disease. // Methods: We performed the first genomewide association study of penetrance and age-at-onset of Parkinson's disease in LRRK2 mutation carriers (776 cases and 1,103 non-cases at...

Objective: The aim of this study was to search for genes/variants that modify the effect of LRRK2 mutations in terms of penetrance and age-at-onset of Parkinson's disease. Methods: We performed the first genome-wide association study of penetrance and age-at-onset of Parkinson's disease in LRRK2 mutation carriers (776 cases and 1,103 non-cases a...

Previous studies on Parkinson’s disease mechanisms have shown dysregulated extracellular transport of α-synuclein and growth factors in the extracellular space. In the human brain these consist of perineuronal nets, interstitial matrices, and basement membranes, each composed of a set of collagens, non-collagenous glycoproteins, proteoglycans, and...

Background: Huntington's disease (HD) is an inherited neurodegenerative disorder caused by an expanded CAG repeat in the HTT gene. It is diagnosed following a standardized examination of motor control and often presents with cognitive decline and psychiatric symptoms. Recent studies have detected genetic loci modifying the age at onset of motor sy...

Background: The mechanisms underlying neurodegeneration in the striatum of Huntingon's Disease (HD) brain are currently unknown. While the striatum is massively degenerated in symptomatic individuals, which makes cellular characterization difficult, it is largely intact in asymptomatic HD gene positive (HD+) individuals. Unfortunately, as striatal...

Variable, glutamine-encoding, CAA interruptions indicate that a property of the uninterrupted HTT CAG repeat sequence, distinct from the length of huntingtin's polyglutamine segment, dictates the rate at which Huntington's disease (HD) develops. The timing of onset shows no significant association with HTT cis-eQTLs but is influenced, sometimes in...

Huntingtons disease (HD) is an inherited neurodegenerative disorder caused by an expanded CAG repeat in HTT. It is diagnosed following a standardized exam of motor control and often presents with cognitive decline and neuropsychiatric signs and symptoms. Recent studies have indicated genetic loci modifying the age at onset of motor symptoms, and it...

The effects of variable, glutamine-encoding, CAA interruptions indicate that a property of the uninterrupted HTT CAG repeat sequence, distinct from huntingtin's polyglutamine segment, dictates the rate at which HD develops. The timing of onset shows no significant association with HTT cis-eQTLs but is influenced, sometimes in a sex-specific manner,...

The mechanisms underlying degeneration of the specific neurons in the striatum of Huntingon's Disease (HD) brain are currently unknown. The striatum is massively degenerated in late stage HD, making examination of post-mortem brain tissue from symptomatic individuals problematic. Striatal tissue is largely intact in the brains of asymptomatic HD po...

Nearly 100 loci have been identified for pulmonary function, almost exclusively in studies of European ancestry populations. We extend previous research by meta-analyzing genome-wide association studies of 1000 Genomes imputed variants in relation to pulmonary function in a multiethnic population of 90,715 individuals of European (N = 60,552), Afri...

Huntington's and Parkinson's Diseases (HD and PD) are neurodegenerative disorders that share some pathological features but are disparate in others. For example, while both diseases are marked by aberrant protein aggregation in the brain, the specific proteins that aggregate and types of neurons affected differ. A better understanding of the molecu...

Crohn’s disease (CD), a form of inflammatory bowel disease, has a higher prevalence in Ashkenazi Jewish than in non-Jewish European populations. To define the role of nonsynonymous mutations, we performed exome sequencing of Ashkenazi Jewish patients with CD, followed by array-based genotyping and association analysis in 2066 CD cases and 3633 heal...

Objective: To investigate the feasibility of microRNA (miRNA) levels in CSF as biomarkers for prodromal Huntington disease (HD). Methods: miRNA levels were measured in CSF from 60 PREDICT-HD study participants using the HTG protocol. Using a CAG-Age Product score, 30 prodromal HD participants were selected based on estimated probability of immin...

Multiple lines of evidence have implicated neuroinflammation as both a cause and an effect of neurodegeneration in Huntington’s disease (HD). Studies of post mortem human HD brains and HD mouse models have demonstrated that the huntingtin protein (mHTT) has neurotoxic effects due to cell-autonomous defects in neurons and through cell-cell interacti...

We have previously shown that exon 1 of the huntingtin gene does not always splice to exon 2 resulting in the production of a small polyadenylated mRNA (HTTexon1) that encodes the highly pathogenic exon 1 HTT protein. The level of this read-through product is proportional to CAG repeat length and is present in all knock-in mouse models of Huntingto...

Nearly 100 loci have been identified for pulmonary function, almost exclusively in studies of European ancestry populations. We extend previous research by meta-analyzing genome-wide association studies of 1000 Genomes imputed variants in relation to pulmonary function in a multiethnic population of 90,715 individuals of European (N=60,552), Africa...

Huntington's disease (HD) is a dominantly inherited neurodegenerative disease caused by an expanded CAG repeat in HTT. Many clinical characteristics of HD such as age at motor onset are determined largely by the size of HTT CAG repeat. However, emerging evidence strongly supports a role for other genetic factors in modifying the disease pathogenesi...

Huntington’s disease (HD) is an autosomal dominant neurodegenerative disease caused by expansion of a CAG trinucleotide repeat in HTT, resulting in an extended polyglutamine tract in huntingtin. We and others have previously determined that the HD-causing expansion occurs on multiple different haplotype backbones, reflecting more than one ancestral...

Huntington’s and Parkinson’s Diseases (HD and PD) are neurodegenerative disorders that share some pathological features but are disparate in others. For example, while both diseases are marked by aberrant protein aggregation in the brain, the specific proteins that aggregate and types of neurons affected differ. A better understanding of the molecu...

Background Next generation sequencing provides a count of RNA molecules in the form of short reads, yielding discrete, often highly non-normally distributed gene expression measurements. Although Negative Binomial (NB) regression has been generally accepted in the analysis of RNA sequencing (RNA-Seq) data, its appropriateness has not been exhaustiv...

Background MicroRNAs (miRNAs) are short, non-coding RNAs that regulate gene expression mainly through translational repression of target mRNA molecules. More than 2700 human miRNAs have been identified and some are known to be associated with disease phenotypes and to display tissue-specific patterns of expression. Methods We used high-throughput s...

Background: Leucine-rich repeat kinase 2 (LRRK2) mutation 6055G→A (Gly2019Ser) accounts for roughly 1% of patients with Parkinson's disease in white populations, 13-30% in Ashkenazi Jewish populations, and 30-40% in North African Arab-Berber populations, although age of onset is variable. Some carriers have early-onset parkinsonism, whereas others...

Background We have previously shown that exon 1 of the huntingtin gene does not always splice to exon 2 resulting in the production of a small polyadenylated mRNA that encodes the highly pathogenic exon 1 HTT protein. The level of this read-through product is proportional to CAG repeat length and present in all knock-in mouse models of HD (with CAG...

Genome-wide association studies (GWAS) have identified the GAK/DGKQ/IDUA region on 4p16.3 among the top three risk loci for Parkinson’s disease (PD), but the specific gene and risk mechanism are unclear. Here, we report transcripts containing the 3’ clathrin-binding domain of GAK identified by RNA deep-sequencing in post-mortem human brain tissue a...

Genome-wide association to GAK25 Expression. Ensembl ID and Gene Symbol are provided for each gene. Estimate represents the effect estimate for association after adjustment for PMI and Age of Death. The Bonferroni-adjusted threshold for significant association is α = 2.11E-06. (XLSX)

Descriptive Characteristics of Brain Samples Studied. (XLSX)

Genome-wide association studies (GWAS) have revealed numerous loci for areal bone mineral density (aBMD). We completed the first GWAS meta-analysis (N = 15,275) of lumbar spine volumetric BMD (vBMD) measured by quantitative computed tomography (QCT), allowing for examination of the trabecular bone compartment. SNPs that were significantly associate...

[This corrects the article DOI: 10.1371/journal.pone.0143563.].

Genome-wide association studies (GWAS) have identified numerous genetic variants associated with complex diseases, but mechanistic insights are impeded by a lack of understanding of how specific risk variants functionally contribute to the underlying pathogenesis. It has been proposed that cis-acting effects of non-coding risk variants on gene expr...

Objective: The goal of this study was to compare the microRNA (miRNA) profile of Parkinson's disease (PD) frontal cortex with normal control brain, allowing for the identification of PD specific signatures as well as study the disease-related phenotypes of onset age and dementia. Methods: Small RNA sequence analysis was performed from prefrontal...

Detailed sample information. Missing information is designated as “NA.”

Results from differential expression and ordinal regression analyses. miRNAs were removed during normalization if they failed to have an average of 2 or more counts. In PD-only analyses, some miRNAs were removed which were not removed in the analyses containing all samples. Information for undetectable miRNAs is flagged as “NA.”

Leptin is an adipocyte-secreted hormone, the circulating levels of which correlate closely with overall adiposity. Although rare mutations in the leptin (LEP) gene are well known to cause leptin deficiency and severe obesity, no common loci regulating circulating leptin levels have been uncovered. Therefore, we performed a genome-wide association s...

Funding for this study was provided by the Academy of Finland (41071, 117787, 118065, 121584, 124282, 126925, 129494, 129322, 129378, 130326, 134309, 134791, 136895, 139635, 250207, 263836, 286284 and 263924); Ahokas Foundation; ALF/LUA research grant in Gothenburg; Amgen; Augustinus Foundation; Becket Foundation; Bristol-Myers Squibb; British Hear...

Background Parkinson disease (PD) is a neurodegenerative disease characterized by the accumulation of alpha-synuclein (SNCA) and other proteins in aggregates termed “Lewy Bodies” within neurons. PD has both genetic and environmental risk factors, and while processes leading to aberrant protein aggregation are unknown, past work points to abnormal l...

Huntington's disease (HD) is an autosomal-dominant neurodegenerative disorder resulting from expansion of CAG repeats in the Huntingtin (HTT) gene. Previous studies have shown mutant HTT can alter expression of genes associated with dysregulated epigenetic modifications. One of the most widely studied chromatin modifications is trimethylated lysine...

Huntington's Disease (HD) is a devastating neurodegenerative disorder that is caused by an expanded CAG trinucleotide repeat in the Huntingtin (HTT) gene. Transcriptional dysregulation in the human HD brain has been documented but is incompletely understood. Here we present a genome-wide analysis of mRNA expression in human prefrontal cortex from 2...

MicroRNAs (miRNAs) are small non-coding RNAs that recognize sites of complementarity of target messenger RNAs, resulting in transcriptional regulation and translational repression of target genes. In Huntington's disease (HD), a neurodegenerative disease caused by a trinucleotide repeat expansion, miRNA dyregulation has been reported, which may imp...

Background: Biomarkers for Huntington's disease progression could accelerate therapeutic developments and improve patient care. Brain microRNAs relating to clinical features of Huntington's disease may represent a potential Huntington's disease biomarker in blood. Objective: This study was undertaken to examine candidate microRNAs in plasma to d...

Importance Identifying measures that are associated with the cytosine-adenine-guanine (CAG) expansion in individuals before diagnosis of Huntington disease (HD) has implications for designing clinical trials.Objective To identify the earliest features associated with the motor diagnosis of HD in the Prospective Huntington at Risk Observational St...

Despite 20 years since its discovery, the gene responsible for Huntington's Disease, HTT, has still not had its function or transcriptional profile completely characterized. In response to a recent report by Ruzo et al. of several novel splice forms of HTT in human embryonic stem cell lines, we have analyzed a set of mRNA sequencing datasets from p...

Background: Huntington's disease (HD) is a dominantly inherited disease caused by a CAG expansion mutation in HTT. The age at onset of clinical symptoms is determined primarily by the length of this CAG expansion but is also influenced by other genetic and/or environmental factors. Objective: Recently, through genome-wide association studies (GW...

Huntington disease (HD) reflects the dominant consequences of a CAG-repeat expansion in HTT. Analysis of common SNP-based haplotypes has revealed that most European HD subjects have distinguishable HTT haplotypes on their normal and disease chromosomes and that ∼50% of the latter share the same major HD haplotype. We reasoned that sequence-level in...

As a Mendelian neurodegenerative disorder, the genetic risk of Huntington's disease (HD) is conferred entirely by an HTT CAG repeat expansion whose length is the primary determinant of the rate of pathogenesis leading to disease onset. To investigate the pathogenic process that precedes disease, we used genome-wide association (GWA) analysis to ide...

Homozygosity has long been associated with rare, often devastating, Mendelian disorders1, and Darwin was one of the first to recognize that inbreeding reduces evolutionary fitness2. However, the effect of the more distant parental relatedness that is common in modern human populations is less well understood. Genomic data now allow us to investigat...

Homozygosity has long been associated with rare, often devastating, Mendelian disorders1, and Darwin was one of the first to recognize that inbreeding reduces evolutionary fitness2. However, the effect of the more distant parental relatedness that is common in modern human populations is less well understood. Genomic data now allow us to investigat...

To investigate epigenetic contributions to Huntington's disease (HD) pathogenesis, we carried out genome-wide mapping of the transcriptional mark, trimethyl-histone H3-lysine 4 (H3K4me3) in neuronal nuclei extracted from prefrontal cortex of HD cases and controls using chromatin immunoprecipitation followed by deep-sequencing. Neuron-specific mappi...

Three-dimensional chromosomal conformations regulate transcription by moving enhancers and reg-ulatory elements into spatial proximity with target genes. Here we describe activity-regulated long-range loopings bypassing up to 0.5 Mb of linear genome to modulate NMDA glutamate receptor GRIN2B expression in human and mouse prefrontal cortex. Distal i...

Multiple biological mechanisms downstream of the expanded CAG repeat have been proposed to contribute to the pathogenesis of Huntington’s disease (HD). Potential therapeutics aimed at many of these mechanisms have shown some benefits in models of disease, but none has yet translated to human HD. A critical issue is knowing which of the potential bi...

We conducted a meta-analysis of Parkinson's disease genome-wide association studies using a common set of 7,893,274 variants across 13,708 cases and 95,282 controls. Twenty-six loci were identified as having genome-wide significant association; these and 6 additional previously reported loci were then tested in an independent set of 5,353 cases and...

In this issue of Neurology®, Rosas et al.(1) present a phase II trial of creatine in Huntington disease (HD). This study is remarkable not only for the demonstration of safety and tolerability, but importantly, the study design establishes the feasibility of clinical trials among premanifest HD individuals. Notably, the trial is undertaken in the d...

Transcriptional dysregulation has long been recognized as central to the pathogenesis of Huntington's disease (HD). MicroRNAs (miRNAs) represent a major system of post-transcriptional regulation, by either preventing translational initiation or by targeting transcripts for storage or for degradation. Using next-generation miRNA sequencing in prefro...

Several methods to correct for multiple testing within a gene region have been proposed. These methods are useful for candidate gene studies, and to fine map gene-regions from GWAs. The Bonferroni correction and permutation are common adjustments, but are overly conservative and computationally intensive, respectively. Other options include calcula...

Although levels of iron are known to be increased in the brains of patients with Parkinson disease (PD), epidemiological evidence on a possible effect of iron blood levels on PD risk is inconclusive, with effects reported in opposite directions. Epidemiological studies suffer from problems of confounding and reverse causation, and mendelian randomi...