PubMed Health⌕ Search

Biomedical subjects

Jan H Veldink

Publications and source records attributed to Jan H Veldink.

8 recordsLinked to original sources
PubMed2026

Whole-genome sequencing implicates rare, low-frequency and structural non-coding variation at the SCN5A locus in Brugada syndrome.

Brugada syndrome (BrS) is an inherited cardiac condition characterized by a hallmark ECG pattern and an increased risk of sudden cardiac death. Central to the aetiology of BrS, the SCN5A region harbours both common non-coding risk variants and rare coding variants that are causative in approximately 20% of patients. However, rare non-coding genetic variation in this region remains largely unexplored. Here, we used whole-genome sequencing (WGS) of 752 European-ancestry BrS cases and 1,827 ancestry-matched controls to identify BrS-associated rare non-coding genetic variation at the SCN5A locus. Sliding-window and cis-regulatory element (CRE)-based rare-variant aggregate testing implicated three conserved CREs, including a dense aggregation of case singleton variants within a 178 bp enhancer in intron 17 of SCN5A which replicated in an independent BrS cohort. Prioritised BrS-associated rare and low-frequency non-coding variants within these elements were predicted to alter cardiac transcription factor motifs, and altered CRE activity in hiPSC-CM luciferase assays or were associated with BrS-relevant ECG endophenotypes in the UK Biobank. Single-variant analysis across the region identified a Bonferroni-significant five-fold case-enriched low-frequency variant within a known CRE in intron 1 of SCN5A, which replicated, was associated with slower cardiac conduction in the UK Biobank and accounted for part of the BrS GWAS signal at this locus. Structural variant analyses identified a 10.5 kb deletion upstream of SCN5A in a BrS case that encompassed a cardiac CRE and reduced sodium current density in a hiPSC-CM model, as well as a 6 kb BrS-enriched retrotransposon insertion in SCN5A that appeared to underlie part of the GWAS signal in this region. Together, these findings implicate rare and low-frequency non-coding variation at the SCN5A locus in BrS susceptibility and demonstrate the value of targeted WGS analysis of key disease loci.

Journal Article↗
PubMed2026

Digenic inheritance of mutations in SPG7 and AFG3L2 causes motor neuron and cerebellar disorders.

BACKGROUND: Biallelic SPG7 mutations cause one of the most common forms of hereditary spastic paraplegia (HSP). Several reports have suggested that heterozygous SPG7 variants may also play a role in HSP, but also in amyotrophic lateral sclerosis (ALS). However, it remains controversial whether heterozygous SPG7 mutations are pathogenic on their own, or if other mechanisms are at play. We recently provided evidence for non-Mendelian inheritance in spastic paraplegia 7 (SPG7), as heterozygous carriers of SPG7 mutations often also carried mutations in other disease-related genes, including AFG3L2, more frequently than expected by chance. Given that SPG7 and AFG3L2 encode interacting subunits of the mitochondrial m-AAA protease complex, we hypothesized that combined heterozygous mutations in these genes may act synergistically to disrupt mitochondrial function and contribute to disease. In this study, we aimed to examine whether digenic heterozygous mutations in SPG7 and AFG3L2 can lead to a spectrum of neurodegenerative disorders. METHODS: We first analyzed genome and exome sequencing data of 6644 unrelated individuals including 4817 motor neuron disorder (MND) and ataxia patients and 1827 controls. We next analyzed an additional 18,748 exome data from rare disease cohorts to further examine the occurrence of variants in SPG7 and AFG3L2. RESULTS: Among the first 4817 MND and ataxia patients, we identified a total of 6 patients, 4 of whom were unrelated, who carried potentially pathogenic variants in both SPG7 and AFG3L2, in contrast to none in 1827 unrelated controls. Further analysis of the 18,748 additional patients with rare disease, as well as a comprehensive literature review, identified 6 more patients, 5 of whom were unrelated, who had digenic mutations in SPG7 and AFG3L2. In the two families we identified, digenic mutations in SPG7 and AFG3L2 perfectly segregated with the disease. The 12 patients reported here exhibited predominant signs of motor neuron and cerebellar involvement. CONCLUSIONS: Our findings demonstrate that digenic inheritance of concurrent heterozygous mutations in SPG7 and AFG3L2 may cause motor neuron and cerebellar disorders. Screening of the entire SPG7 and AFG3L2 genes in genetically undiagnosed cases of MND and spastic ataxia may help to increase the diagnostic yield.

Humans↗
PubMed2007

The association between H63D mutations in HFE and amyotrophic lateral sclerosis in a Dutch population.

BACKGROUND: Mutations in HFE, a gene defect that can disrupt iron metabolism, have been implicated in increasing the risk of developing amyotrophic lateral sclerosis (ALS). OBJECTIVE: To further establish the association between ALS and HFE mutations by investigating whether HFE mutations are associated with an increased risk of developing ALS in a population in The Netherlands and by pooling our results with those from previous studies. DESIGN: Retrospective study. SETTING: Tertiary referral center for neuromuscular disorders. PARTICIPANTS: Genotyping for 2 common HFE mutations was performed in 289 patients with ALS and 5886 population-based controls in The Netherlands between January 1, 2000, and December 31, 2004. MAIN OUTCOME MEASURES: Development of ALS and clinical phenotype were compared among the different HFE genotypes, adjusting for known prognostic factors such as age at onset and sex. RESULTS: Homozygosity for H63D was associated with an increased risk of developing ALS (odds ratio [OR], 2.2; 95% confidence interval [CI], 1.1-4.1). After pooling our results with those from previous studies, a positive association between H63D homozygotes (OR, 2.7; 95% CI, 1.7-4.4), heterozygotes (OR, 1.5; 95% CI, 1.0-2.1), and mutation carriers (OR, 1.7; 95% CI, 1.1-2.5) was found. Within the patient group, heterozygosity for the H63D mutation was associated with a higher age at onset. CONCLUSIONS: These findings suggest that H63D mutations in HFE play a role in the pathogenesis of ALS in various populations. This association might involve a later-onset subset of ALS.

Adult↗
PubMed2004

The future of motor neuron disease: the challenge is in the genes.

Adult-onset motor neuron disease (MND) includes sporadic and familial forms of amyotrophic lateral sclerosis (ALS), lower motor neuron disease including progressive and segmental spinal muscular atrophy (LMND) and primary lateral sclerosis (PLS). ALS/MND can be considered to be a spectrum of neurodegenerative diseases characterised by a preferential degeneration of upper and/or lower motor neurons. ALS and LMND have a complex multifactorial aetiology and a large clinical variability. This combination warrants an increasing genomics approach in future research. Genomics is the structural and functional study of genomes--i. e. the complete set of chromosomes and the genes they contain. Several methods may help to understand gene functions, and every method has led to its own "omics". The study of the complex relationship between on the one hand genomics data, transcriptomics data, proteomics data, and interactomics data and on the other hand the phenotype, is called "phenomics". In phenomics, the extensive and detailed phenotyping by the clinician is a prerequisite for meaningful associations. As a consequence, in ALS/MND clinicians have the task to agree about different clinical subtypes in order to make these associations and hence to gain further insight into the complex pathogenesis and identification of diagnostic markers in ALS/MND. Also, several new approaches in the treatment of ALS/MND are here discussed, including the viral delivery of protective compounds, RNA-interference, and stem cell therapy. Further, we argue that a future challenge is to allow for patients to have early access to multidisciplinary centres with specialist knowledge of ALS/MND. These centres can apply specific models of care for people with ALS/MND, but must be designed in a patient-centred format. Ultimately, these models should be assessed according to their outcomes.

Forecasting↗
PubMed2004

CGP 3466B has no effect on disease course of (G93A) mSOD1 transgenic mice.

BACKGROUND: There is an accumulating body of evidence that apoptosis is involved in the motor neuron death that occurs in ALS, and in the (G93A) mSOD1 transgenic mouse model (mSOD1 mice). CGP 3466B, a tricyclic propargylamine structurally related to (-)-deprenyl, was found to inhibit apoptosis in a wide variety of in vitro and in vivo models. We therefore studied the effect of CGP 3466B in mSOD1 mice. METHODS: As the effect of CGP 3466B was previously reported to have a bell-shaped curve, we performed a dose-ranging study. High-copy G93A mSOD1 mice were treated subcutaneously from the age of 50 days until death with four concentrations of CGP 3466B (0.39 microg kg(-1), 3.9 microg kg(-1), 39 microg kg(-1), and 390 microg kg(-1)). Behavioural tests were performed daily to determine disease onset, disease progression and survival. At the age of 110 days, two mice per group were sacrificed for histopathological analysis of the lumbar ventral horn and for semiquantitative analysis of motor neuron number. RESULTS: We observed no effect on disease onset, disease progression, or survival of the mice. We also did not observe a significant effect on the number of motor neurons due to CGP 3466B. CONCLUSIONS: We conclude that in high-copy G93A mSOD1 mice, chronic subcutaneous treatment with CGP 3466B offers no clinical benefit.

Amyotrophic Lateral Sclerosis↗
PubMed2003

A randomized sequential trial of creatine in amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a fatal disease with no cure. In a transgenic mouse model of ALS, creatine monohydrate showed a promising increase in survival. We performed a double-blind, placebo-controlled, sequential clinical trial to assess the effect of creatine monohydrate on survival and disease progression in patients with ALS. Between June 2000 and December 2001, 175 patients with probable, probable-laboratory supported, or definite ALS were randomly assigned to receive either creatine monohydrate or placebo 10 gm daily. A sequential trial design was used with death, persistent assisted ventilation, or tracheostomy as primary end points. Secondary outcome measurements were rate of decline of isometric arm muscle strength, forced vital capacity, functional status, and quality of life. The trial was stopped when the null hypothesis of indifference was accepted. Creatine did not affect survival (cumulative survival probability of 0.70 in the creatine group vs 0.68 in the placebo group at 12 months, and 0.52 in the creatine group vs 0.47 in the placebo group at 16 months), or the rate of decline of functional measurements. Creatine intake did not cause important adverse reactions. This placebo-controlled trial did not find evidence of a beneficial effect of creatine monohydrate on survival or disease progression in patients with ALS.

Aged↗
PubMed2002

Euthanasia and physician-assisted suicide among patients with amyotrophic lateral sclerosis in the Netherlands.

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a disease that causes progressive paralysis leading to respiratory failure. Patients with ALS may consider physician-assisted suicide. However, it is not known how many patients, if given the option, would actually decide to end their lives by physician-assisted suicide or euthanasia nor at what stage of the disease they would choose to do so. METHODS: We identified physicians of 279 patients in the Netherlands with a diagnosis of ALS who died between 1994 and 1999. Physicians were asked to fill out a validated questionnaire about the end-of-life decisions that were made. Of 241 eligible physicians, 203 returned the questionnaire (84 percent). RESULTS: Of the 203 patients, 35 (17 percent) chose euthanasia and died that way. An additional six patients (3 percent) died as a result of physician-assisted suicide. Patients to whom religion was important were less likely to have died as a result of euthanasia or physician-assisted suicide. The choice of euthanasia or physician-assisted suicide was not associated with any particular characteristics of the disease or of the patient's care, nor was it associated with income or educational level. Disability before death was significantly more severe in patients who died as a result of euthanasia than among those who died in other ways. Physician-assisted suicide appeared to occur somewhat earlier in the course of the disease than did euthanasia. An additional 48 patients (24 percent) received palliative treatment, which probably shortened their lives. CONCLUSIONS: In the Netherlands, we found that one in five patients with ALS died as a result of euthanasia or physician-assisted suicide.

Advance Directives↗