Systematic Review of Newborn Screening Programmes for Spinal Muscular Atrophy.

Spinal muscular atrophy (SMA) is a genetic neuromuscular disorder causing the degeneration of motor neurons in the spinal cord. Recent studies suggest greater effectiveness of treatment in the presymptomatic stage. This systematic review synthesises findings from 37 studies (and 3 overviews) of newborn screening for SMA published up to November 2023 across 17 countries to understand the methodologies used; test accuracy performance; and timing, logistics and feasibility of screening. All studies screened for the homozygous deletion of SMN1 exon 7. Most (28 studies) used RT-PCR as the initial test on dried blood spots (DBSs), while nine studies also reported second-tier tests on DBSs for screen-positive cases. Babies testing positive on DBSs were referred for confirmatory testing via a range of methods. Observed SMA birth prevalence ranged from 1 in 4000 to 1 in 20,000. Most studies reported no false-negative or false-positive cases (therefore had a sensitivity and specificity of 100%). Five studies reported either one or two false-negative cases each (total of six cases; three compound heterozygotes and three due to system errors), although some false-negatives may have been missed due to lack of follow-up of negative results. Eleven studies reported false-positive cases, some being heterozygous carriers or potentially related to heparin use. Time to testing and treatment varied between studies. In conclusion, several countries have implemented newborn screening for SMA in the last 5 years using a variety of methods. Implementation considerations include processes for timely initial and confirmatory testing, partnerships between screening and neuromuscular centres, and timely treatment initiation.

Genomic Copy Number Analysis Using Droplet Digital PCR: A Simple Method with EvaGreen Single-Color Fluorescent Design.

Droplet digital PCR (ddPCR) is an emerging method for the absolute quantification of PCR products, and it can detect DNA copy numbers accurately. It analyzes the end-point absolute fluorescence signals of the PCR-positive droplets and calculates the target concentration. EvaGreen is a nonspecific double-stranded DNA-binding fluorescent dye, and the ddPCR system also supports assays using this cost-effective hydrolysis probe. Here, we describe a simple method of quantification for DNA copy numbers using the EvaGreen single-color fluorescent design.

Biological aging markers in blood and brain tissue indicate age acceleration in alcohol use disorder.

BACKGROUND: Alcohol use disorder (AUD) is associated with increased mortality and morbidity risk. A reason for this could be accelerated biological aging, which is strongly influenced by disease processes such as inflammation. As recent studies of AUD show changes in DNA methylation and gene expression in neuroinflammation-related pathways in the brain, biological aging represents a potentially important construct for understanding the adverse effects of substance use disorders. Epigenetic clocks have shown accelerated aging in blood samples from individuals with AUD. However, no systematic evaluation of biological age measures in AUD across different tissues and brain regions has been undertaken. METHODS: As markers of biological aging (BioAge markers), we assessed Levine's and Horvath's epigenetic clocks, DNA methylation telomere length (DNAmTL), telomere length (TL), and mitochondrial DNA copy number (mtDNAcn) in postmortem brain samples from Brodmann Area 9 (BA9), caudate nucleus, and ventral striatum (N = 63-94), and in whole blood samples (N = 179) of individuals with and without AUD. To evaluate the association between AUD status and BioAge markers, we performed linear regression analyses while adjusting for covariates. RESULTS: The majority of BioAge markers were significantly associated with chronological age in all samples. Levine's epigenetic clock and DNAmTL were indicative of accelerated biological aging in AUD in BA9 and whole blood samples, while Horvath's showed the opposite effect in BA9. No significant association of AUD with TL and mtDNAcn was detected. Measured TL and DNAmTL showed only small correlations in blood and none in brain. CONCLUSIONS: The present study is the first to simultaneously investigate epigenetic clocks, telomere length, and mtDNAcn in postmortem brain and whole blood samples in individuals with AUD. We found evidence for accelerated biological aging in AUD in blood and brain, as measured by Levine's epigenetic clock, and DNAmTL. Additional studies of different tissues from the same individuals are needed to draw valid conclusions about the congruence of biological aging in blood and brain.

Staging of COVID-19 disease; using selected laboratory profiles for prediction, prevention and management of severe SARS-CoV-2 infection in Africa-review.

There are many uncertainties on the future management of the coronavirus disease 19 (COVID-19) in Africa. By July 2021, Africa had lagged behind the rest of the world in Covid-19 vaccines uptake, accounting for just 1.6% of doses administered globally. During that time COVID 19 was causing an average death rate of 2.6% in Africa, surpassing the then global average of 2.2%. There were no clear therapeutic guidelines, yet inappropriate and unnecessary treatments may have led to unwanted adverse events such as worsening of hyperglycemia and precipitating of ketoacidosis in administration of steroid therapy. in order to provide evidence-based policy guidelines, we examined peer-reviewed published articles in PubMed on COVID 19, or up-to date data, we focused our search on publications from 1st May 2020 to 15th July, 2021. For each of the studies, we extracted data on pathophysiology, selected clinical chemistry and immunological tests, clinical staging and treatment. Our review reports a gross unmet need for vaccination, inadequate laboratory capacity for immunological tests and the assessment of individual immune status, clinical staging and prediction of disease severity. We recommend selected laboratory tools in the assessment of individual immune status, prediction of disease severity and determination of the exact timing for suitable therapy, especially in individuals with co-morbidities.

Effect of Soybean Protein Concentrate Preparation on Copy Numbers and Structural Characteristics of DNA from Genetically Modified Soybean.

To regulate the degradation of transgenic DNA and lay theoretical foundations for the rational utilization of genetically modified (GM) products, variations in copy numbers and structural characteristics of DNA from GM soybean event GTS 40-3-2 during soybean protein concentrate (SPC) preparation were evaluated. Results showed that defatting and the first ethanol extraction were key procedures inducing DNA degradation. After these two procedures, copy numbers of the lectin and cp4 epsps targets decreased by more than 4 × 108, occupying 36.88-49.30% of the total copy numbers from raw soybean. Atomic force microscopy images visually revealed the degradation of DNA that thinned and shortened during SPC preparation. Circular dichroism spectra suggested a lower helicity of DNA from defatted soybean kernel flour and a conformation transition of DNA from B-type to A-type after ethanol extraction. The fluorescence intensity of DNA decreased during SPC preparation, verifying the DNA damage along this preparation chain.

Lung mitochondrial DNA copy number, inflammatory biomarkers, gene transcription and gene methylation in vapers and smokers.

BACKGROUND: Mitochondrial DNA copy number (mtCN) maintains cellular function and homeostasis, and is linked to nuclear DNA methylation and gene expression. Increased mtCN in the blood is associated with smoking and respiratory disease, but has received little attention for target organ effects for smoking or electronic cigarette (EC) use. METHODS: Bronchoscopy biospecimens from healthy EC users, smokers (SM), and never-smokers (NS) were assessed for associations of mtCN with mtDNA point mutations, immune responses, nuclear DNA methylation and gene expression using linear regression. Ingenuity pathway analysis was used for enriched pathways. GEO and TCGA respiratory disease datasets were used to explore the involvement of mtCN-associated signatures. FINDINGS: mtCN was higher in SM than NS, but EC was not statistically different from either. Overall there was a negative association of mtCN with a point mutation in the D-loop but no difference within groups. Positive associations of mtCN with IL-2 and IL-4 were found in EC only. mtCN was significantly associated with 71,487 CpGs and 321 transcripts. 263 CpGs were correlated with nearby transcripts for genes enriched in the immune system. EC-specific mtCN-associated-CpGs and genes were differentially expressed in respiratory diseases compared to controls, including genes involved in cellular movement, inflammation, metabolism, and airway hyperresponsiveness. INTERPRETATION: Smoking may elicit a lung toxic effect through mtCN. While the impact of EC is less clear, EC-specific associations of mtCN with nuclear biomarkers suggest exposure may not be harmless. Further research is needed to understand the role of smoking and EC-related mtCN on lung disease risks. FUNDING: The National Cancer Institute, the National Heart, Lung, and Blood Institute, the Food and Drug Administration Center for Tobacco Products, the National Center For Advancing Translational Sciences, and Pelotonia Intramural Research Funds.

Integration analyses of structural variations and differential gene expression associated with beef fatty acid profile in Nellore cattle.

This study aimed to integrate analyses of structural variations and differentially expressed genes (DEGs) associated with the beef fatty acid (FA) profile in Nellore cattle. Copy numbers variation (CNV) detection was performed using the penncnv algorithm and CNVRuler software in 3794 genotyped animals through the High-Density Bovine BeadChip. In order to perform the genomic wide association study (GWAS), a total of 963 genotyped animals were selected to obtain the intramuscular lipid concentration and quantify the beef FA profile. A total of 48 animals belonging to the same farm and management lot were extracted from the 963 genotyped and phenotyped animals to carry out the transcriptomic and differentially expressed gene analyses. The GWAS with extreme groups of FA profiles was performed using a logistic model. A total of 43, 42, 66 and 35 significant CNV regions (p < 0.05) for saturated, monounsaturated, polyunsaturated and omega 3 and 6 fatty acids were identified respectively. The paired-end sequencing of 48 samples was performed using the Illumina HiSeq2500 platform. Real-time quantitative PCR was used to validate the DEGs identified by RNA-seq analysis. The results showed several DEGs associated with the FA profile of Longissimus thoracis, such as BSCL2 and SAMD8. Enriched terms as the cellular response to corticosteroid (GO:0071384) and glucocorticoid stimulus (GO:0071385) could be highlighted. The identification of structural variations harboring candidate genes for beef FA must contribute to the elucidation of the genetic basis that determines the beef FA composition of intramuscular fat in Nellore cattle. Our results will contribute to the identification of potential biomarkers for complex phenotypes, such as the FA profile, to improve the reliability of the genomic predictions including pre-selected variants using differentiated weighting in the genomic models.

The association between mitochondrial DNA abundance and stroke: A combination of multivariable-adjusted survival and Mendelian randomization analyses.

BACKGROUND AND AIMS: Mitochondrial dysfunction is associated with increased reactive oxygen species (ROS) that are thought to drive disease risk, including stroke. We investigated the association between mtDNA abundance, as a proxy measure of mitochondrial function, and incident stroke, using multivariable-adjusted survival and Mendelian Randomization (MR) analyses. METHODS: Cox-proportional hazard model analyses were conducted to assess the association between mtDNA abundance, and incident ischemic and hemorrhagic stroke over a maximum of 14-year follow-up in European-ancestry participants from UK Biobank. MR was conducted using independent (R2 < 0.001) lead variants for mtDNA abundance (p < 5 × 10-8) as instrumental variables. Single-nucleotide polymorphism (SNP)-ischemic stroke associations were derived from three published open source European-ancestry results databases (cases/controls): MEGASTROKE (60,341/454,450), UK Biobank (2404/368,771) and FinnGen (10,551/202,223). MR was performed per study, and results were subsequently meta-analyzed. RESULTS: In total, 288,572 unrelated participants (46% men) with mean (SD) age of 57 (8) years were included in the Cox-proportional hazard analyses. After correction for considered confounders (BMI, hypertension, cholesterol, T2D), no association was found between low versus high mtDNA abundance and ischemic (HR: 1.06 [95% CI: 0.95, 1.18]) or hemorrhagic (HR: 0.97 [95% CI: 0.82, 1.15]) stroke. However, in the MR analyses after removal of platelet count-associated SNPs, we found evidence for an association between genetically-influenced mtDNA abundance and ischemic stroke (odds ratio, 1.17; confidence interval, 1.03, 1.32). CONCLUSIONS: Although the results from both multivariable-adjusted prospective and basis MR analyses did not show an association between low mtDNA and increased risk of ischemic stroke, in-depth MR sensitivity analyses may suggest evidence for a causal relationship.

Absolute Quantification of Nav1.5 Expression by Targeted Mass Spectrometry.

Nav1.5 is the pore forming α-subunit of the cardiac voltage-gated sodium channel that initiates cardiac action potential and regulates the human heartbeat. A normal level of Nav1.5 is crucial to cardiac function and health. Over- or under-expression of Nav1.5 can cause various cardiac diseases ranging from short PR intervals to Brugada syndromes. An assay that can directly quantify the protein amount in biological samples would be a priori to accurately diagnose and treat Nav1.5-associated cardiac diseases. Due to its large size (>200 KD), multipass transmembrane domains (24 transmembrane passes), and heavy modifications, Nav1.5 poses special quantitation challenges. To date, only the relative quantities of this protein have been measured in biological samples. Here, we describe the first targeted and mass spectrometry (MS)-based quantitative assay that can provide the copy numbers of Nav1.5 in cells with a well-defined lower limit of quantification (LLOQ) and precision. Applying the developed assay, we successfully quantified transiently expressed Nav1.5 in as few as 1.5 million Chinese hamster ovary (CHO) cells. The obtained quantity was 3 ± 2 fmol on the column and 3 ± 2 × 104 copies/cell. To our knowledge, this is the first absolute quantity of Nav1.5 measured in a biological sample.

Predominance of genomically defined A lineage of HPV16 over D lineage in Indian patients from eastern India with squamous cell carcinoma of the cervix in association with distinct oncogenic phenotypes.

Human papillomavirus type-16 (HPV16) is classified into lineages, A, B, C and D and 10 sub-lineages portraying variable infectivity, persistence, and cytological outcomes, however, with geographical variations. Our objective was to delineate the distinctive features of lineages among cervical squamous cell carcinoma (SCC) in the eastern region of India. A total of 145 SCC cases and 24 non-malignant specimens, harboring episomal HPV16, were included. The presence of higher proportion of lineage A over D was observed among SCC cases (86.89% A1, 8.97% D1 and 4.14% D2), while only A1 sub-lineage viruses were found among control specimens. Among the A1 viruses, an association of variants in the E5 (Y44L, I65V), E6 (L83V) genes and LCR: C7577T with SCC, with combined Odd's ratio (95% CI) of 20.5(4.61-91.25) was observed. Network analyses revealed the presence of 10 clades of lineage A viruses comprising of 64 HPV16 genomes harboring the risk alleles. High episomal HPV16 DNA copy numbers (adjusted p-value= 0.0271) and E7 mRNA expression (p-value=0.000017) predominated in SCC with lineage A, over D. Our study highlights the distinctive modalities of oncogenicity among different HPV16 lineages.

Quantitative high-confidence human mitochondrial proteome and its dynamics in cellular context.

Mitochondria are key organelles for cellular energetics, metabolism, signaling, and quality control and have been linked to various diseases. Different views exist on the composition of the human mitochondrial proteome. We classified >8,000 proteins in mitochondrial preparations of human cells and defined a mitochondrial high-confidence proteome of >1,100 proteins (MitoCoP). We identified interactors of translocases, respiratory chain, and ATP synthase assembly factors. The abundance of MitoCoP proteins covers six orders of magnitude and amounts to 7% of the cellular proteome with the chaperones HSP60-HSP10 being the most abundant mitochondrial proteins. MitoCoP dynamics spans three orders of magnitudes, with half-lives from hours to months, and suggests a rapid regulation of biosynthesis and assembly processes. 460 MitoCoP genes are linked to human diseases with a strong prevalence for the central nervous system and metabolism. MitoCoP will provide a high-confidence resource for placing dynamics, functions, and dysfunctions of mitochondria into the cellular context.

Genome Copy Number Quantification Revealed That the Ethanologenic Alpha-Proteobacterium Zymomonas mobilis Is Polyploid.

The alpha-proteobacterium Zymomonas mobilis is a promising biofuel producer, based on its native metabolism that efficiently converts sugars to ethanol. Therefore, it has a high potential for industrial-scale biofuel production. Two previous studies suggested that Z. mobilis strain Zm4 might not be monoploid. However, a systematic analysis of the genome copy number is still missing, in spite of the high potential importance of Z. mobilis. To get a deep insight into the ploidy level of Z. mobilis and its regulation, the genome copy numbers of three strains were quantified. The analyses revealed that, during anaerobic growth, the lab strain Zm6, the Zm6 type strain obtained from DSMZ (German Collection of Microorganisms), and the lab strain Zm4, have copy numbers of 18.9, 22.3 and 16.2, respectively, of an origin-adjacent region. The copy numbers of a terminus-adjacent region were somewhat lower with 9.3, 15.8, and 12.9, respectively. The values were similar throughout the growth curves, and they were only slightly downregulated in late stationary phase. During aerobic growth, the copy numbers of the lab strain Zm6 were much higher with around 40 origin-adjacent copies and 17 terminus-adjacent copies. However, the cells were larger during aerobic growth, and the copy numbers per µm3 cell volume were rather similar. Taken together, this first systematic analysis revealed that Z. mobilis is polyploid under regular laboratory growth conditions. The copy number is constant during growth, in contrast to many other polyploid bacteria. This knowledge should be considered in further engineering of the strain for industrial applications.

Linking Microbes to Their Genes at Single Cell Level with Direct-geneFISH.

Direct-geneFISH is a Fluorescence In Situ Hybridization (FISH) method that directly links gene presence, and thus potential metabolic capabilities, to cell identity. The method uses rRNA-targeting oligonucleotide probes to identify cells and dsDNA polynucleotide probes carrying multiple molecules of the same fluorochrome to detect genes. In addition, direct-geneFISH allows quantification of the cell fraction carrying the targeted gene and the number of target genes per cell. It can be applied to laboratory cultures, for example, enrichments and phage infections, and to environmental samples. This book chapter describes the main steps of the direct-geneFISH protocol: probe design and synthesis, the "core" direct-geneFISH protocol and lastly, microscopy and data analysis.

A measles outbreak in Kansai International Airport, Japan, 2016: Analysis of the quantitative difference and infectivity of measles virus between patients who are immunologically naive versus those with secondary vaccine failure.

Since the elimination of the measles virus, patients with vaccination records for the measles-containing vaccine have increased in Japan. According to several studies, the transmission risk from previously immunized patients, especially those with secondary vaccine failure (SVF), is lower than that from those with primary measles infections. Immunological features of SVF were identified per specific immunoglobulin G (IgG) induction with high avidity and high plaque reduction neutralization antibody concentration. However, the virological features of SVF have not been well investigated. To examine not only immunological but also virological differences between SVF and immunologically naive patients, throat swabs and blood and urine specimens of 25 patients with confirmed measles infection after an outbreak at the Kansai International Airport in 2016 were analyzed. Patients were categorized as naive (n = 3) or with SVF (n = 22) based on measles-specific IgG antibody concentrations and their avidity. Virus isolation and quantitative real-time polymerase chain reaction were performed to quantify the viral load in clinical specimens and estimate the infectivity in each specimen. The number of viral genome copies in the blood specimens of those with SVF was significantly different and approximately 1 out of 100 of that in immunologically naive patients. However, genome copy numbers in throat swabs and urine specimens were not significantly different between the groups. The virus was isolated only from those in the naive group. Our study indicated low transmission risk of the virus in patients with SVF.

Rare Pathogenic Copy Number Variation in the 16p11.2 (BP4-BP5) Region Associated with Neurodevelopmental and Neuropsychiatric Disorders: A Review of the Literature.

Copy number variants (CNVs) play an important role in the genetic underpinnings of neuropsychiatric/neurodevelopmental disorders. The chromosomal region 16p11.2 (BP4-BP5) harbours both deletions and duplications that are associated in carriers with neurodevelopmental and neuropsychiatric conditions as well as several rare disorders including congenital malformation syndromes. The aim of this article is to provide a review of the current knowledge of the diverse neurodevelopmental disorders (NDD) associated with 16p11.2 deletions and duplications reported in published cohorts. A literature review was conducted using the PubMed/MEDLINE electronic database limited to papers published in English between 1 January 2010 and 31 July 2020, describing 16p11.2 deletions and duplications carriers' cohorts. Twelve articles meeting inclusion criteria were reviewed from the 75 articles identified by the search. Of these twelve papers, eight described both deletions and duplications, three described deletions only and one described duplications only. This study highlights the heterogeneity of NDD descriptions of the selected cohorts and inconsistencies concerning accuracy of data reporting.

Salivary Amylase Gene Copy Number Is Associated with the Obesity and Inflammatory Markers in Children.

BACKGROUND: We have recently shown that the copy number of salivary amylase (AMY1) gene was significantly decreased, and the obesity-related salivary biomarkers resistin, MCP-1, TNF-α, IL-6, and CRP were significantly increased in overweight/obese children compared to normal weight. This study aimed to evaluate the association of AMY1 copy number variant (CNV) with obesity and inflammatory markers. Seventy-six participants aged between 6 and 10 years have participated, and the saliva samples were collected along with the anthropometric measurements. METHODS: AMY1 copy number was analyzed by 3D digital PCR, and obesity-related biomarkers were performed with a Bioplex multiplex analyzer. RESULTS: The mean AMY1 copy number was higher in normal weight (7.90 ± 0.38) compared to the overweight/obese group (6.20 ± 0.29). The association of AMY1 CNV with obesity and inflammatory markers showed significant negative correlation [CRP, ß = -0.238 (p < 0.05); resistin, ß = -0.25 (p < 0.05); MCP-1, ß = -0.304 (p < 0.01)] except for complement factor D, TNF α and IL-6. The anti-inflammatory cytokine, IL-10 reported a positive correlation with AMY1 copy number with a ß = 0.268 (p < 0.05). The multivariable model adjusted with age and gender depicted a similar correlation with obesity markers. CONCLUSION: Our results report that AMY1 CNV is associated with obesity and inflammatory biomarkers in children's saliva sample.

Accurate Inference of Tumor Purity and Absolute Copy Numbers From High-Throughput Sequencing Data.

Inference of absolute copy numbers in tumor genomes is one of the key points in the study of tumor genesis. However, the mixture of tumor and normal cells poses a big challenge to this task. Accurate estimation of tumor purity (i.e., the fraction of tumor cells) is a necessary step to solve this problem. In this paper, we propose a new approach, AITAC, to accurately infer tumor purity and absolute copy numbers in a tumor sample by using high-throughput sequencing (HTS) data. In contrast to many existing algorithms for estimating tumor purity, which usually rely on pre-detected mutation genotypes (heterogeneity and homogeneity), AITAC just requires read depths (RDs) observed at the regions with copy number losses. AITAC creates a non-linear model to correlate tumor purity, observed and expected RDs. It adopts an exhaustive search strategy to scan tumor purity in a wide range, and chooses the tumor purity that minimizes the deviation between observed RDs and expected ones as the optimal solution. We apply the proposed approach to both simulation and real sequencing data sets and demonstrate its performance by comparing with two classical approaches. AITAC is freely available at https://github.com/BDanalysis/aitac and can be expected to become a useful approach for researchers to analyze copy numbers in cancer genome.

Supernumerary B Chromosomes and Plant Genome Changes: A Snapshot of Wild Populations of Aegilops speltoides Tausch (Poaceae, Triticeae).

In various eukaryotes, supernumerary B chromosomes (Bs) are an optional genomic component that affect their integrity and functioning. In the present study, the impact of Bs on the current changes in the genome of goatgrass, Aegilops speltoides, was addressed. Individual plants from contrasting populations with and without Bs were explored using fluorescence in situ hybridization. In parallel, abundances of the Ty1-copia, Ty3-gypsy, and LINE retrotransposons (TEs), and the species-specific Spelt1 tandem repeat (TR) in vegetative and generative spike tissues were estimated by real-time quantitative PCR. The results revealed: (i) ectopic associations between Bs and the regular A chromosomes, and (ii) cell-specific rearrangements of Bs in both mitosis and microgametogenesis. Further, the copy numbers of TEs and TR varied significantly between (iii) genotypes and (iv) different spike tissues in the same plant(s). Finally, (v) in plants with and without Bs from different populations, genomic abundances and/or copy number dynamics of TEs and TR were similar. These findings indicate that fluctuations in TE and TR copy numbers are associated with DNA damage and repair processes during cell proliferation and differentiation, and ectopic recombination is one of the mechanisms by which Bs play a role in genome changes.

Salivary AMY1 Copy Number Variation Modifies Age-Related Type 2 Diabetes Risk.

BACKGROUND: Copy number variation (CNV) in the salivary amylase gene (AMY1) modulates salivary α-amylase levels and is associated with postprandial glycemic traits. Whether AMY1-CNV plays a role in age-mediated change in insulin resistance (IR) is uncertain. METHODS: We measured AMY1-CNV using duplex quantitative real-time polymerase chain reaction in two studies, the Boston Puerto Rican Health Study (BPRHS, n = 749) and the Genetics of Lipid-Lowering Drug and Diet Network study (GOLDN, n = 980), and plasma metabolomic profiles in the BPRHS. We examined the interaction between AMY1-CNV and age by assessing the relationship between age with glycemic traits and type 2 diabetes (T2D) according to high or low copy numbers of the AMY1 gene. Furthermore, we investigated associations between metabolites and interacting effects of AMY1-CNV and age on T2D risk. RESULTS: We found positive associations of IR with age among subjects with low AMY1-copy-numbers in both studies. T2D was marginally correlated with age in participants with low AMY1-copy-numbers but not with high AMY1-copy-numbers in the BPRHS. Metabolic pathway enrichment analysis identified the pentose metabolic pathway based on metabolites that were associated with both IR and the interactions between AMY1-CNV and age. Moreover, in older participants, high AMY1-copy-numbers tended to be associated with lower levels of ribonic acid, erythronic acid, and arabinonic acid, all of which were positively associated with IR. CONCLUSIONS: We found evidence supporting a role of AMY1-CNV in modifying the relationship between age and IR. Individuals with low AMY1-copy-numbers tend to have increased IR with advancing age.