Publications by authors named "Sumi John"

Background: Numerous studies have linked mitochondrial dysfunction to the development of type 2 diabetes (T2D) by affecting glucose-stimulated insulin secretion in pancreatic beta cells and reducing oxidative phosphorylation in insulin-responsive tissues. Given the strong genetic underpinnings of T2D, research has explored the connection between mitochondrial DNA haplogroups, specific variants, and the risk and comorbidities of T2D. For example, haplogroups F, D, M9, and N9a have been linked to an elevated risk of T2D across various populations.

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  • The study investigates the relationship between mitochondrial DNA (mtDNA) variants and obesity risk in Kuwaiti and Qatari populations, to address the high obesity prevalence in these regions.
  • Analysis of whole exome sequencing data from 1,112 participants identified haplogroup R as having a protective effect against obesity, with statistically significant results even after adjusting for age and sex.
  • While several mtDNA variants showed initial associations with obesity, they lost significance after further testing; the findings suggest haplogroup R could serve as a biomarker for obesity risk, warranting more research for confirmation.
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  • The study investigates Autosomal recessive polycystic kidney disease (ARPKD) in Kuwait, focusing on understanding its genetic diversity and clinical presentation to improve management strategies.
  • A total of 60 individuals with suspected ARPKD were examined, revealing a significant mortality rate (33.3%) in newborns, while survivors exhibited a variety of health complications, including hypertension and enlarged cystic kidneys.
  • The research identified 12 genetic mutations in over half of the cases, emphasizing the need for personalized diagnostic and treatment approaches for ARPKD.
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This study unveils verapamil's compelling cytoprotective and proliferative effects on pancreatic β-cells amidst diabetic stressors, spotlighting its unforeseen role in augmenting cholecystokinin (CCK) expression. Through rigorous investigations employing MIN6 β-cells and zebrafish models under type 1 and type 2 diabetic conditions, we demonstrate verapamil's capacity to significantly boost β-cell proliferation, enhance glucose-stimulated insulin secretion, and fortify cellular resilience. A pivotal revelation of our research is verapamil's induction of CCK, a peptide hormone known for its role in nutrient digestion and insulin secretion, which signifies a novel pathway through which verapamil exerts its therapeutic effects.

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Objectives: Type 2 diabetes (T2D) is a metabolic disease of major public health concern. It impacts peripheral tissues and the central nervous system, leading to systemic dysmetabolism and neurocognitive impairments, including memory deficits, anxiety, and depression. The metabolic determinants of these neurocognitive impairments remain unidentified.

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gene, encoding hepatocyte nuclear factor 6, is involved in pancreas and liver development. mutations impair the function of pancreatic β-cells and control a transcriptional/epigenetic machinery regulating endocrine development. Homozygous nonsense and missense mutations at _p.

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Type 1 diabetes (T1D) is characterized by the progressive destruction of pancreatic β-cells, leading to insulin deficiency and lifelong dependency on exogenous insulin. Higher estimates of heritability rates in monozygotic twins, followed by dizygotic twins and sib-pairs, indicate the role of genetics in the pathogenesis of T1D. The incidence and prevalence of T1D are alarmingly high in Kuwait.

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Introduction: Circadian rhythm maintains the sleep-wake cycle in biological systems. Various biological activities are regulated and modulated by the circadian rhythm, disruption of which can result in onset of diseases. Robust rhythms of phosphorylation profiles and abundances of PERIOD (PER) proteins are thought to be the master keys that drive circadian clock functions.

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Background: Autosomal dominant polycystic kidney disease (ADPKD) is the most common renal monogenic disease, characterized by bilateral accumulation of renal fluid-filled cysts leading to progressive renal volume enlargement and gradual impairment of kidney function, often resulting in end-stage renal disease. Kuwait could provide valuable genetic insights about ADPKD, including intrafamilial phenotypic variation, given its large household size. This study aims to provide a comprehensive description of the pathogenic variants linked to ADPKD in the Kuwaiti population using multiple genetic analysis modalities and to describe and analyse the ADPKD phenotypic spectrum in terms of kidney function, kidney volume and renal survival.

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There has recently been a growing interest in examining the role of epigenetic modifications, such as DNA methylation, in the etiology of type 1 diabetes (T1D). This study aimed to delineate differences in methylation patterns between T1D-affected and healthy individuals by examining the genome-wide methylation of individuals from three Arab families from Kuwait with T1D-affected mono-/dizygotic twins and non-twinned siblings. Bisulfite sequencing of DNA from the peripheral blood of the affected and healthy individuals from each of the three families was performed.

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Genetic variants responsible for Maturity-Onset-Diabetes of the Young (MODY) in Kuwait were investigated. A newly established a National Referral Clinic, the Dasman Diabetes Institute (DDI-NRC), assessed forty-five members from 31 suspected MODY families by whole exome sequencing. Thirty-three of the 45 samples were independently sequenced at the DDI-NRI, Exeter University, UK ( https://www.

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  • COVID-19 is impacting global health, economies, and daily life, with infection and death rates differing significantly across countries.
  • Analyzing 2431 SARS-CoV-2 sequences revealed 1010 unique mutations and seven clusters, with notable genetic differences between samples from Asia, Europe, and North America.
  • The study suggests that genetic recombination among strains may increase the virus's severity and complicate treatment efforts, potentially explaining the severe second wave of COVID-19 in numerous countries.
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With the tremendous advancements in genome sequencing technology in the field of pharmacogenomics, data have to be made accessible to be more efficiently utilized by broader clinical disciplines. Physicians who require the drug-genome interactome information, have been challenged by the complicated pharmacogenomic star-based classification system. We present here an end-to-end web-based pharmacogenomics tool, PharmaKU, which has a comprehensive easy-to-use interface.

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  • Whole-exome sequencing was used to analyze genetic variations related to obesity in a group of 288 native Arabs in Kuwait, revealing mitochondrial DNA's role in obesity risk.
  • Variants and haplogroups were identified, showing that haplogroup R decreases obesity risk while haplogroup L increases it; significant differences in mitochondrial mutations between obese and non-obese groups were also noted.
  • Findings confirm the effectiveness of whole-exome sequencing in studying mitochondrial haplogroups and their association with obesity for the first time in this specific population.
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The severity of the new COVID-19 pandemic caused by the SARS-CoV-2 virus is strikingly variable in different global populations. SARS-CoV-2 uses as a cell receptor, protease, and peptidase to invade human cells. Here, we investigated 1,378 whole-exome sequences of individuals from the Middle Eastern populations (Kuwait, Qatar, and Iran) to explore natural variations in the , and genes.

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COVID-19 is caused by Severe Acute Respiratory Syndrome Coronavirus-2, which has infected over thirty eight million individuals worldwide. Emerging evidence indicates that COVID-19 patients are at a high risk of developing coagulopathy and thrombosis, conditions that elevate levels of D-dimer. It is believed that homocysteine, an amino acid that plays a crucial role in coagulation, may also contribute to these conditions.

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While the Arabian population has a high prevalence of metabolic disorders, it has not been included in global studies that identify genetic risk loci for metabolic traits. Determining the transferability of such largely Euro-centric established risk loci is essential to transfer the research tools/resources, and drug targets generated by global studies to a broad range of ethnic populations. Further, consideration of populations such as Arabs, that are characterized by consanguinity and a high level of inbreeding, can lead to identification of novel risk loci.

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Consanguineous populations of the Arabian Peninsula, which has seen an uncontrolled rise in type 2 diabetes incidence, are underrepresented in global studies on diabetes genetics. We performed a genome-wide association study on the quantitative trait of fasting plasma glucose (FPG) in unrelated Arab individuals from Kuwait (discovery-cohort:n = 1,353; replication-cohort:n = 1,196). Genome-wide genotyping in discovery phase was performed for 632,375 markers from Illumina HumanOmniExpress Beadchip; and top-associating markers were replicated using candidate genotyping.

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Consanguineous populations of the Arabian Peninsula have been underrepresented in global efforts that catalogue human exome variability. We sequenced 291 whole exomes of unrelated, healthy native Arab individuals from Kuwait to a median coverage of 45X and characterised 170,508 single-nucleotide variants (SNVs), of which 21.7% were 'personal'.

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Abnormal blood lipid levels are influenced by genetic and lifestyle/dietary factors. Although many genetic variants associated with blood lipid traits have been identified in Europeans, similar data in Middle Eastern populations are limited. We performed a genome-wide association study with Arab individuals (discovery cohort: 1,353; replication cohort: 1,176) from Kuwait to identify possible associations of genetic variants with high lipid levels.

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Assessing the distinct prevalence or absence of genetic variants associated with differential response to the anticoagulant medication of warfarin in different population groups is actively pursued by pharmacogenomics community. Populations from Arabian Peninsula are underrepresented in such studies. By way of examining exome- and genome-wide genotype data from 1395 Arab individuals in Kuwait, we report distinct occurrence of warfarin response-related variants rs12460590_A/CYP2A7, rs2108622_T/CYP4F2, rs2884737_C/VKORC1 and distinct absence of rs11150606_C/PRSS53 in Kuwaiti population.

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Objective: Despite alarming obesity levels in the Arabian Peninsula, its population lacks convincingly identified genetic determinants of obesity. A genome-wide association study was performed for obesity-related anthropometric traits in Arabs and to decipher mechanisms by which the variants mediate traits.

Methods: The Illumina HumanOmniExpress BeadChip was used to genotype 1,353 Arab individuals (largely with Class I obesity) from Kuwait.

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Despite a high prevalence of metabolic trait related diseases in Arabian Peninsula, there is a lack of convincingly identified genetic determinants for metabolic traits in this population. Arab populations are underrepresented in global genome-wide association studies. We genotyped 1965 unrelated Arab individuals from Kuwait using Cardio-MetaboChip, and tested SNP associations with 13 metabolic traits.

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Objective: To characterize the underlying genetic and molecular defects in a consanguineous family with lifelong blood disorder manifested with thrombocytopenia (low platelets count) and anemia.

Methods: Genetic linkage analysis, exome sequencing, and functional genomics were carried out to identify and characterize the defective gene.

Results: We identified a novel truncation mutation (p.

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Kuwaiti native population comprises three distinct genetic subgroups of Persian, "city-dwelling" Saudi Arabian tribe, and nomadic "tent-dwelling" Bedouin ancestry. Bedouin subgroup is characterized by presence of 17% African ancestry; it owes it origin to nomadic tribes of the deserts of Arabian Peninsula and North Africa. By sequencing whole genome of a Kuwaiti male from this subgroup at 41X coverage, we report 3,752,878 SNPs, 411,839 indels, and 8451 structural variations.

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