Genomics T7 Past Paper 2024-2025 PDF

Genomics 2024-2025 T7 Ana Karina Mendes | [email protected] 11-11-2024  What is epigenetics and how it regulates gene expression? AKMendes Genomics 2024-2025 2 ...

Genomics 2024-2025 T7 Ana Karina Mendes | [email protected] 11-11-2024  What is epigenetics and how it regulates gene expression? AKMendes Genomics 2024-2025 2  Epigenetics and regulation of gene activity The term “epigenetics” is used to describe heritable alterations in gene expression that are not encoded in the DNA sequence In response to a physiological stimulus In different disease states In a particular cell type AKMendes Genomics 2024-2025 3 Epigenetic mechanisms of genome regulation Adapted from Chow et al., Stem Cell Res Ther 2013, 4(4):97 AKMendes Genomics 2024-2025 4  Epigenetics and Obesity Epigenetic changes can regulate how genes involved in metabolism, appetite, fat storage, and energy balance are expressed, potentially contributing to the development of obesity AKMendes Genomics 2024-2025 5  Factors Influencing Epigenetic Changes in Obesity 1.Prenatal and Early-Life Factors Maternal Nutrition: The nutritional status of a mother during pregnancy can have a lasting impact on the child’s epigenome, influencing susceptibility to obesity. For example: Undernutrition or overnutrition during pregnancy can lead to epigenetic modifications in genes that regulate metabolism, predisposing the child to obesity and metabolic disorders. Gestational Diabetes: Exposure to a high-glucose environment in utero can alter the baby’s epigenome, affecting insulin sensitivity and fat storage. 2.Diet and Lifestyle High-Fat or High-Sugar Diets: Poor dietary habits can lead to changes in DNA methylation and histone modifications, affecting genes that regulate appetite and metabolism. Physical Activity: Exercise can reverse or modify some epigenetic changes, promoting better metabolic health. Chronic Stress: Stress can alter the expression of genes involved in cortisol regulation, which affects fat storage and metabolism. AKMendes Genomics 2024-2025 6  DNA Methylation is a reversible process DNA Methylation (1) and (2) -> gene silencing DNA Demethylation (3) and (4) -> gene expression Neuropsychopharmacology Reviews (2013) 38, 23-38; doi:10.1038/npp.2012.112 Adapted from Lurlaro et al., Current Opinion in Genetics & Development 2017, 101-109 AKMendes Genomics 2024-2025 7  CpG islands Stretches of DNA roughly 1000 base pairs long that have a higher CpG density than the rest of the genome but often are not methylated The majority of gene promoters, roughly 70%, reside within CpG islands As many transcription factor binding sites are GC rich, CpG islands enhance the accessibility of DNA and promote transcription factor binding AKMendes Genomics 2024-2025 8  Normal and cancer genomes exhibit distinct DNA methylation profiles AKMendes Genomics 2024-2025 9 Genomic Imprinting X chromosome inactivation DNA Methylation Silencing of Transposable Elements Tissue-specific Gene Expression AKMendes Genomics 2024-2025 10  High-throughput technologies to study DNA Methylation AKMendes Genomics 2024-2025 11 Procedures for genome-wide DNA Methylation analysis AKMendes Genomics 2024-2025 12 Procedures for genome-wide DNA Methylation analysis AKMendes Genomics 2024-2025 13  Bisulfite Conversion AKMendes Genomics 2024-2025 14  Whole Genome Bisulfite Sequencing (WGBS) Mono_BS iDC_BS AKMendes Genomics 2024-2025 15  EpiTYPER MassARRAY AKMendes Genomics 2024-2025 16  RNA Sequencing AKMendes Genomics 2024-2025 17 Combined analysis of DNA methylation and RNA expression AKMendes Genomics 2024-2025 18