Studies assessing the impact of amylase genes copy number (CN) on adiposity report conflicting findings in different global populations, likely reflecting the impact of ancestral and ethnic-specific environment and lifestyle on selection at the amylase loci. Here, we leverage population size and detailed adiposity measures from a large population biobank to resolve confounding effects and determine the relationship between salivary (AMY1) and pancreatic (AMY2A) amylase genes CN and adiposity in 2935 Qatari individuals who underwent whole-genome sequencing (WGS) as part of the Qatar Genome Programme. We observe a negative association between AMY1 CNs and trunk fat percentage in the Qatari population (P = 7.50 × 10−3) and show that Qataris of Arab descent have significantly lower CN at AMY1 (P = 1.32 × 10−10) as well as less favorable adiposity and metabolic profiles (P < 1.34 × 10−8) than Qataris with Persian ancestry. Indeed, lower AMY1 CN was associated with increased total and trunk fat percentages in Arabs (P < 4.60 × 10−3) but not in Persians. Notably, overweight and obese Persians reported a significant trend towards dietary restraint following weight gain compared to Arabs (P = 4.29 × 10−5), with AMY1 CN showing negative association with dietary self-restraint (P = 3.22 × 10−3). This study reports an association between amylase gene CN and adiposity traits in a large Middle Eastern population. Importantly, we leverage rich biobank data to demonstrate that the strength of this association varies with ethnicity, and may be influenced by population-specific behaviors that also contribute to adiposity traits.

Type 1 diabetes (T1D) is an autoimmune condition where the body’s immune cells destroy their insulin-producing pancreatic beta cells leading to dysregulated glycaemia. Individuals with T1D control their blood glucose through exogenous insulin replacement therapy, often using multiple daily injections or pumps. However, failure to accurately mimic intrinsic glucose regulation results in glucose fluctuations and long-term complications impacting key organs such as the heart, kidneys, and/or the eyes. It is well established that genetic and environmental factors contribute to the initiation and progression of T1D, but recent studies show that epigenetic modifications are also important. Here, we discuss key epigenetic modifications associated with T1D pathogenesis and discuss how recent research is finding ways to harness epigenetic mechanisms to prevent, reverse, or manage T1D.

While de novo mutations (DNMs) are key to genetic diversity, they are also responsible for a high number of rare disorders. To date, no study has systematically examined the rate and distribution of DNMs in multiplex families in highly consanguineous populations. Leveraging WGS profiles of 645 individuals in 146 families, we implemented a combinatorial approach using 3 complementary tools for DNM discovery in 353 unique trio combinations. We found a total of 27,168 DNMs (median: 70 single-nucleotide and 6 insertion-deletions per individual). Phasing revealed around 80% of DNMs were paternal in origin. Notably, using whole-genome methylation data of spermatogonial stem cells, these DNMs were significantly more likely to occur at highly methylated CpGs (OR: 2.03; p value = 6.62 × 10−11). We then examined the effects of consanguinity and ethnicity on DNMs, and found that consanguinity does not seem to correlate with DNM rate, and special attention has to be considered while measuring such a correlation. Additionally, we found that Middle-Eastern families with Arab ancestry had fewer DNMs than African families, although not significant (p value = 0.16). Finally, for families with diseased probands, we examined the difference in DNM counts and putative impact across affected and unaffected siblings, but did not find significant differences between disease groups, likely owing to the enrichment for recessive disorders in this part of the world, or the small sample size per clinical condition. This study serves as a reference for DNM discovery in multiplex families from the globally under-represented populations of the Middle-East.

Mandibulofacial dysostosis with microcephaly (MFDM) is a rare genetic disorder inherited in an autosomal dominant pattern. Major characteristics include developmental delay, craniofacial malformations such as malar and mandibular hypoplasia, and ear anomalies. Here, we report a 4.5-yr-old female patient with symptoms fitting MFDM. Using whole-genome sequencing, we identified a de novo start-codon loss (c.3G > T) in the EFTUD2. We examined EFTUD2 expression in the patient by RNA sequencing and observed a notable functional consequence of the variant on gene expression in the patient. We identified a novel variant for the development of MFDM in humans. To the best of our knowledge, this is the first report of a start-codon loss in EFTUD2 associated with MFDM.

A number of hyperglycemia- and dyslipidemia- triggered pathways, and numerous protein-encoding genes boosting the diabetic retinopathy (DR) progression. Evolving data suggests vast number of microRNAs(miRNAs) which exhibit no protein-coding capacity, are expressed and play key roles in DR pathogenesis. Purpose: of this pilot is to identify the miRNAs involved in pathways altered in lipid metabolism and dyslipidemia and to explore the association of dyslipidemia with the progression of DR. Methodology: 460 patients with diabetes type 2 (T2D) aged 23-77 years including 37 with DR and 490 matched healthy controls age range 18-74, from Qatar biobank cohort. The circulating miRNA profile was assessed in this pilot study. Logistic regression analysis was performed on the phenotypic data to investigate the level of association between A1C, low-density lipoproteins (LDL) and Triglycerides (TG) covariants and the miRNA expression profile in T2D with and without DR. Results: The most broadly characterized miRNAs in lipid metabolism are miR-33a/b; however, we identified another three miRNAs (miR-133b, miR-142-3p and miR-483-5p) shared between LDL and TG phenotypes. In particular, miR-133b appeared to be directly linked to retinal degeneration identified through our miRNA-target disease interaction network analysis. Our results indicated that all three miRNAs are significantly associated with VEGFR2 mediated vascular permeability, insulin signaling, apoptosis, EGFR, TGF-Beta signaling, cellular senescence and degradation pathways leading to the DR initiation than development. Conclusions: miRNAs are not only small regulators of lipid metabolism, but vital influencers in lipid homeostasis and lipoproteins formation and secretion. Dysregulation of these regulatory elements most likely augment the underlying metabolic flaws perceived in lipid disorders and related microvascular complications. Disclosure A. S. Akil: None. S. Subash padmajeya: None. L. A. Jerman: None. T. Habib: None. A. Al-kurbi: None. E. E. Aliyev: None. M. El anbari: None. K. Fakhro: None. Funding Qatar National Research Fund (NPRP9-229-3-041)