Publications by authors named "Natalie Twine"

Epistasis refers to changes in the effect on phenotype of a unit of genetic information, such as a single nucleotide polymorphism or a gene, dependent on the context of other genetic units. Such interactions are both biologically plausible and good candidates to explain observations which are not fully explained by an additive heritability model. However, the search for epistasis has so far largely failed to recover this missing heritability.

View Article and Find Full Text PDF

Antimicrobial resistance (AMR) poses a significant global health threat, resulting in 4.96 million deaths in 2019, with projections reaching 10 million by 2050. This resistance, primarily due to the overuse of antibiotics, complicates the treatment of infections caused by various microorganisms, including the gram-negative bacterium Escherichia coli.

View Article and Find Full Text PDF

Genomic information is increasingly used to inform medical treatments and manage future disease risks. However, any personal and societal gains must be carefully balanced against the risk to individuals contributing their genomic data. Expanding our understanding of actionable genomic insights requires researchers to access large global datasets to capture the complexity of genomic contribution to diseases.

View Article and Find Full Text PDF

Coronary artery disease (CAD) has the highest disease burden worldwide. To manage this burden, predictive models are required to screen patients for preventative treatment. A range of variables have been explored for their capacity to predict disease, including phenotypic (age, sex, BMI and smoking status), medical imaging (carotid artery thickness) and genotypic.

View Article and Find Full Text PDF

Genetic data is limited and generating new datasets is often an expensive, time-consuming process, involving countless moving parts to genotype and phenotype individuals. While sharing data is beneficial for quality control and software development, privacy and security are of utmost importance. Generating synthetic data is a practical solution to mitigate the cost, time and sensitivities that hamper developers and researchers in producing and validating novel biotechnological solutions to data intensive problems.

View Article and Find Full Text PDF

Alzheimer's disease (AD) is a complex genetic disease, and variants identified through genome-wide association studies (GWAS) explain only part of its heritability. Epistasis has been proposed as a major contributor to this 'missing heritability', however, many current methods are limited to only modelling additive effects. We use VariantSpark, a machine learning approach to GWAS, and BitEpi, a tool for epistasis detection, to identify AD associated variants and interactions across two independent cohorts, ADNI and UK Biobank.

View Article and Find Full Text PDF

Random forests (RFs) are a widely used modelling tool capable of feature selection via a variable importance measure (VIM), however, a threshold is needed to control for false positives. In the absence of a good understanding of the characteristics of VIMs, many current approaches attempt to select features associated to the response by training multiple RFs to generate statistical power via a permutation null, by employing recursive feature elimination, or through a combination of both. However, for high-dimensional datasets these approaches become computationally infeasible.

View Article and Find Full Text PDF
Article Synopsis
  • Newborn screening (NBS) is a vital public health measure that identifies treatable genetic diseases, but many conditions remain untested due to a lack of suitable methods; targeted gene sequencing (TGS) offers a potential solution.
  • A TGS panel was created to screen 164 genes associated with various inherited conditions, and a streamlined laboratory process was established to manage the samples efficiently and address challenges seen with broader genome sequencing.
  • Results showed high accuracy in the assay with over 99% sensitivity and 100% specificity, demonstrating that TGS can effectively expand NBS programs and may prove cost-effective for screening more conditions.
View Article and Find Full Text PDF

There are inherent complexities and tensions in achieving a responsible balance between safeguarding patients' privacy and sharing genomic data for advancing health and medical science. A growing body of literature suggests establishing patient genomic data ownership, enabled by blockchain technology, as one approach for managing these priorities. We conducted an online survey, applying a mixed methods approach to collect quantitative (using scale questions) and qualitative data (using open-ended questions).

View Article and Find Full Text PDF

Objective: European and Australian guidelines for cystic fibrosis (CF) reproductive carrier screening recommend testing a small number of high frequency CF causing variants, rather than comprehensive CFTR sequencing. The study objective was to determine variant detection rates of commercially available targeted reproductive carrier screening tests in Australia.

Methods: Next-generation DNA sequencing of the CFTR gene was performed on 2552 individuals from a whole population sample to identify CF causing variants.

View Article and Find Full Text PDF

The breakdown of toll-like receptor (TLR) tolerance results in tissue damage, and hyperactivation of the TLRs and subsequent inflammatory consequences have been implicated as risk factors for more severe forms of disease and poor outcomes from various diseases including COVID-19 and metabolic (dysfunction) associated fatty liver disease (MAFLD). Here we provide evidence that membrane bound O-acyltransferase domain containing 7 (MBOAT7) is a negative regulator of TLR signalling. MBOAT7 deficiency in macrophages as observed in patients with MAFLD and in COVID-19, alters membrane phospholipid composition.

View Article and Find Full Text PDF

New SARS-CoV-2 variants emerge as part of the virus' adaptation to the human host. The Health Organizations are monitoring newly emerging variants with suspected impact on disease or vaccination efficacy as Variants Being Monitored (VBM), like Delta and Omicron. Genetic changes (SNVs) compared to the Wuhan variant characterize VBMs with current emphasis on the spike protein and lineage markers.

View Article and Find Full Text PDF

Complex genetic diseases may be modulated by a large number of epistatic interactions affecting a polygenic phenotype. Identifying these interactions is difficult due to computational complexity, especially in the case of higher-order interactions where more than two genomic variants are involved. In this paper, we present BitEpi, a fast and accurate method to test all possible combinations of up to four bi-allelic variants (i.

View Article and Find Full Text PDF
Article Synopsis
  • Tryptophan (TRP) is a key amino acid linked to the kynurenine pathway (KP), which can become overactive due to inflammation and is associated with neurodegenerative diseases like amyotrophic lateral sclerosis (ALS).
  • ALS can be either familial or sporadic, with genetic factors playing a significant role in both forms, particularly in sporadic ALS (SALS), where multiple gene variants may increase susceptibility alongside environmental interactions.
  • Research on 614 Australian SALS cases identified several genes related to TRP metabolism that showed unique variants, suggesting these may be risk factors for ALS through their effects on the KP and neuroinflammation.
View Article and Find Full Text PDF

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease caused by the progressive degeneration of motor neurons. Recently, genetic variants in GLT8D1 and ARPP21 were associated with ALS in a cohort of European descent. A synergistic relationship was proposed between ALS associated variants in GLT8D1 and ARPP21.

View Article and Find Full Text PDF
Article Synopsis
  • ALS is a neurodegenerative disorder leading to paralysis and death, with about 10% of cases having a familial history while others appear sporadic.
  • Research suggests familial ALS mutations may also occur in sporadic cases, indicating some sporadic cases could be unrecognized familial instances.
  • A study on 83 familial ALS cases used identity-by-descent analysis to identify genetic links, revealing unique haplotypes for mutations and helping to connect familial and sporadic cases for better understanding of disease variability.
View Article and Find Full Text PDF

Background: Many traits and diseases are thought to be driven by >1 gene (polygenic). Polygenic risk scores (PRS) hence expand on genome-wide association studies by taking multiple genes into account when risk models are built. However, PRS only considers the additive effect of individual genes but not epistatic interactions or the combination of individual and interacting drivers.

View Article and Find Full Text PDF

Background: Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease with phenotypic and genetic heterogeneity. Approximately 10% of cases are familial, while remaining cases are classified as sporadic. To date, >30 genes and several hundred genetic variants have been implicated in ALS.

View Article and Find Full Text PDF
Article Synopsis
  • The study aims to investigate the role of the CHCHD10 protein and its genetic variations in ALS (amyotrophic lateral sclerosis) and FTD (frontotemporal dementia) patients in Australia.
  • Researchers analyzed genetic data from a significant number of ALS and FTD cases, and examined CHCHD10 protein levels in postmortem tissues and a transgenic mouse model.
  • The findings indicate that no new disease-related genetic variants were found, but a reduction in CHCHD10 protein levels in neuronal tissues suggests its potential role in ALS/FTD, particularly as a late event in the disease progression linked to TDP-43 pathology.
View Article and Find Full Text PDF

Background: Chlorotoxin (Cltx) isolated from scorpion venom is an established tumor targeting and antiangiogenic peptide. Radiolabeled Cltx therapeutic (I-TM601) yielded promising results in human glioma clinical studies, and the imaging agent tozuleristide, is under investigation in CNS cancer studies. Several binding targets have previously been proposed for Cltx but none effectively explain its pleiotropic effects; its true target remains ambiguous and is the focus of this study.

View Article and Find Full Text PDF

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterised by the loss of upper and lower motor neurons. ALS exhibits high phenotypic variability including age and site of onset, and disease duration. To uncover epigenetic and transcriptomic factors that may modify an ALS phenotype, we used a cohort of Australian monozygotic twins (n = 3 pairs) and triplets (n = 1 set) that are discordant for ALS and represent sporadic ALS and the two most common types of familial ALS, linked to C9orf72 and SOD1.

View Article and Find Full Text PDF

Long-term in vitro expansion of bone marrow stromal (skeletal) stem cells (also known as human mesenchymal stem cells [hMSC]) is associated with replicative senescence and impaired functions. We have previously reported that telomerization of hMSC through hTERT overexpression led to bypassing a replicative senescence phenotype and improved in vitro and in vivo functions. However, the molecular consequence of telomerization is poorly characterized.

View Article and Find Full Text PDF

Reprogramming of immunosuppressive tumor microenvironment (TME) by targeting alternatively activated tumor associated macrophages (M2TAM), myeloid-derived suppressor cells (MDSC), and regulatory T cells (Tregs), represents a promising strategy for developing novel cancer immunotherapy. Prostaglandin E2 (PGE), an arachidonic acid pathway metabolite and mediator of chronic inflammation, has emerged as a powerful immunosuppressor in the TME through engagement with one or more of its 4 receptors (EP1-EP4). We have developed E7046, an orally bioavailable EP4-specific antagonist and show here that E7046 has specific and potent inhibitory activity on PGE-mediated pro-tumor myeloid cell differentiation and activation.

View Article and Find Full Text PDF