Essay On Epigenetic Programming By Maternal Behavior

The study greatly helped in understanding the mechanism of nutrition and epigenetic inheritance to the child while in the womb. It has been shown through animal studies that a methyl rich diet of the mother gives a progeny with a highly methylated DNA. Specifically, studies in mice have shown that diet affects the Agouti gene (present in all mammals) when the gene is not methylated the mice shows a yellow coat, a fatter complexion and is likely to develop diabetes and cancer. Unlike the healthy mice

The terrible event allowed a remarkable scientific insight into the world of epigenetics. Studies were taken out on those who survived the famine. These victims only suffered one period of malnutrition in their lives so scientists were able to observe the long term effects this single event caused. A major aspect studied was the consequences the famine had on mothers and their unborn children. Results found that if the child was conceived during the time the mother was well fed and then born when their mother was malnourished for the final three months of pregnancy, the child was born underweight. Studying these children throughout their lives showed that they remained small. Whereas children whose time of conception was whilst there mother was malnourished for the first three months of pregnancy, then born when their mother was well fed again, where born abnormally larger. These children continued to stay large and developed higher obesity rates than the rest of the population. Epigenetic mechanisms have been proposed to underline these associations. Studies indicated a link between prenatal nutritional factors and DNA methylation. It was found that Methylation was lower in individuals prenatally exposed to the famine. Meaning the mothers personal lifestyle issues caused the DNA methylation process to alter her DNA which she then passed down to her child. (Naturalhistorymag,

How is it that two identical twins with the exact same DNA and the same environment can be very different? (Coutney Griffin 2012) Cortney Griffin elaborated on how her journey of having twins lead her to a deeper understanding of what epigenetics truly is. This talk, although vastly viewed in biochemistry classes including at the University of Texas of El Paso, differs from the scholarly article “Epigenetics and human disease: translating basic biology into clinical applications” by David Rodenhiser and Mellissa Mann. Their most prominent similarities and differences can be separated into audience and purpose, rhetorical appeals, and structure and delivery.

To understand epigenetics and transgenerational epigenetics in greater detail we need to obtain a clearer picture of the underlying molecular mechanisms. Lim and Brunet (2013) revealed that environmental stimuli can influence the chromatin structure by noncoding RNAs- including siRNA (small interfering RNA, worm), piRNA ((Piwi-interacting RNA, worm and fly), viRNA (small interfering RNAs derived from virus, worm), miRNA (micro RNA, mice)- DNA methylation (mice, rat) and histone modification (with the help of Histone methyltransferase poteins)- H3K4me2/3 (worm), H3K36me3 (worm), H3K36me3 (worm, fly), H3K9me2/3 (worm, fly), H3K27me3 (mice, human). Prion proteins might also play role (yeast). These changes might influence the metabolics, which changes the expression of different chemicals and are themselves potential environmental stress factors; thus, they could initiate epigenomic changes. Chromatin modifications

ONE of biology’s hottest topics is epigenetics. The term itself covers a multitude of sins. Strictly speaking, it refers to the regulation of gene expression by the chemical modification of DNA, or of the histone proteins in which DNA is usually wrapped. This modification is either the addition of methyl groups (a carbon atom and three hydrogens) to the DNA or of acetyl groups (two carbons, three hydrogens and an oxygen) to the histones. Methylation switches genes off. Acetylation switches them on. Since, in a multicellular organism, different cells need different genes to be active, such regulation is vital.

The regulation of epigenetics plays a major role in development because it contains markers that control the expression

Studies have shown that our ancestors experience’s may leave a mark on our genes. Geneticists were surprised to find that epigenetic change could be passed down from parent to child. A study from Randy Jirtle of Duke University showed that when female mice are fed a diet rich in methyl groups, the fur pigment of subsequent offspring is permanently altered without changing the DNA. Madrid, Szyf and Meaney considered a hypothesis: “If diet and chemicals can cause epigenetic changes, could certain experiences — child neglect, drug abuse or other severe stresses — also set off epigenetic changes to the DNA inside the neurons of a person’s brain?” This study states that the biology of DNA will stay the same how ever psychological and behavioral tendencies are inherited.

Epigenetics is the study of trait variations that are resulted not from the DNA but environmental factors that determines which gene switches on and off and how they are viewed as a whole. In the beginning of Chapter 7, the author brings about studies done to see if a mother’s behavior could influence the child’s behavior without having a change in the DNA. In this case, the experimenters were looking for the problem of obesity. The studies proved their point that if a pregnant mother chooses an unhealthy diet during pregnancy, then the result increases the chances of childhood obesity in the child. This can give rise to diabetes which is heavily influenced by obesity.

Starting with figure 1, the major question that the figure is attempting to answer is how LG-ABN maternal care affects cytosine methylation of the GR promotor and how CpG methylation in the GR promotor region, exon 1 base 7 promoter differ between high and low LG-ABN (maternal care) groups. It is trying to figure out whether there is a causal relationship between LG-ABN and DNA methylation of the pups and whether or not timing of maternal care/age of the pups have anything to do with the different levels of DNA methylation. There are both positive and negative control groups for figure 1. The positive control is the group of offspring that received low amount of LG-ABN from their mothers and show high amounts of C-methylation. The negative control is the group of offspring that

The effects of gene methylation can be harnessed to suppress or promote gene expression on humans. We can choose genes we prefer and induce expression using drugs that can target specific cells and allows the methylation cascade. Epigenetic medications can possibly treat depression, anxiety, and PTSD where psychiatric drugs have failed to do so

Genomic imprinting does not follow the standard Mendelian rules of inheritance. Instead the single allele from a specific parent is preferably expressed over the other allele even if both are normal, functional versions (“Genetic Analysis”). The amount of methylation on the cytosine nucleotides of a sequence called the imprinting control region (ICR) governs the imprinted genes. In general increased methylation decreases expression of the gene and vice versa.

Epigenetic modifications to the human genome have increasingly become the subject of scientific research due to a presumptive role in the pathology and progression of degenerative diseases. Conventionally, methylation of a nucleotide residue is associated with gene repression, whereas acetylation of a nucleotide residue is associated with gene expression. Through a member of the DNA methyltransferase protein family, the formation of 5-methylcytosine (5mC) from a previously unmodified cytosine residue is a classic representation of a widely-occurring, principal epigenetic modification event. This process is subject to dynamic regulation and as such, the regulatory mechanisms have yet to be elucidated. In regards to demethylation of these particular residues, humans lack a corresponding methylcytosine specific DNA glycosylase; however, a potential alternate pathway has been identified. Catalyzed by the human ten eleven translocation 1 (TET1) proteins, oxidation of 5mC results in formation of 5-hydroxymethylcytosine (5hmC); when 5hmC is further subject to oxidation, 5-formylcytosine (5fC) is produced. These oxidized derivatives are suspected to be substrates designated for removal by the base excision repair pathway.

Earlier studies in this field demonstrate the presence of certain factors that can establish a link between these variation, These factors, are known as epigenetic factors, which cause changes in the way a gene is expressed without causing any actual change in the DNA sequence. Such changes are most commonly brought about by a modification in certain specific regions of the DNA strand and is known as DNA methylation,

This paper, written for the course ‘Molecular microbiology and epigenetics’ is a summary of two

The scientific studies conducted for epigenetics have given light and has helped disprove a common fact that DNA is a person’s destiny. A person's destiny is instead due to multiple factors. These factors range from the mother’s diet during pregnancy to the person’s lifestyle (Watters 33). An experiment conducted by Randy Jirtle, a professor at Duke University, has proven the mother’s diet during pregnancy has a profound impact on child's epigenome. The experiment took mice that have the agouti gene and bred them. Typically, the child would have the agouti gene like the parents, which would make them yellow, fat, and prone to diseases, but it did not. The offspring did not phonetically posses the agouti gene but were slender brown mice. This was due to the mother’s rich diet of methyl foods rich during pregnancy which altered the epigenome and phonetically turned off the agouti gene (Watters 33). These methyl-rich foods are the type of victims usually found in the victim's pills pregnant woman take so this data can be applied to humans like most mice experiments and results from them. Scientists have conducted other studies and have found that identical twins having the same DNA can be drastically different by the time they are twenty years old due to their different experiences in life (Fraga, Mario F., et al). Epigenetics marks are affected by experiences a