Caleb Pan Report # 1 Problem The problem of the experiment is how a diet in a pregnant mother can change genes in her offspring. Scientists used a fat yellow mouse that carried a gene made the color of their coat different and leads to obesity, diabetes, and cancer in the mouse. If scientists can figure out this strange occurrence, they are able to help human beings in perfecting their diets and may even lead to better drugs to minimize the risk of cancer and obesity. Observations During methylation, a process in which biological mechanisms other than mutations that affect how a gene or genes function, a methyl group attaches to a gene. This process stops genes that are not needed by a cell.
The genes on one of the two X chromosomes in each female cell are silenced by this process, which are not needed. Another observation of methyl groups and other small molecules help relax the coils of DNA so that inactive genes are active and vice versa. The tight coiled DNA may inactivate genes, so, methylation helps relaxes it and, therefore, genes that were inactivated become active once again. Scientific Law The methyl groups that creates the process of methylation, come from the foods we eat. They are a non-permanent way of "tweaking" the genes in a non-permanent way (mutation).
In this instance, the yellow mouse was fed with vitamin supplements until it gave birth to a normal mouse. A scientist chose a strand of DNA that happens to have transposon. This strand contains the past of viral infections. This acts as an on and off switch for genes. The methyl groups attach to the strand, and shut off the whole gene to prevent infections. Hypothesis Scientists wonder if more methyl groups are introduced in the a mice's diet can affect the infected gene to a greater extent making a lesser chance of mice being born with the defective gene.
The results agreed with the hypothesis because in the diagram shown in the article, the pregnant mouse fed with a normal diet produced more mice with obesity while the other mouse fed with the modified diet produced less offspring with obesity. Theories The reason why less mice are born with defects is because the methyl groups act as an on and off switch. It deactivates unneeded genes and activates genes that are needed for normal living. The deactivated genes from the pregnant mouse goes through to its offspring, too.
Words transposon - A segment of DNA that is capable of independently replicating itself and inserting the copy into a new position within the same or another chromosome or plasmid. agouti gene - The alternation of light and dark bands of color in the fur of various animals, producing a grizzled appearance. methylation - Addition of methyl groups. In histo-chemistry methylation is used to esterify carboxyl groups and remove sulfate groups by treating tissue sections with hot methanol in the presence of hydrochloric acid. epigenetic's - According to the epigenetic view of differentiation, the cell makes a series of choices (some of which may have no obvious phenotypic expression and are spoken of as determination events) that lead to the eventual differentiated state. Thus, selective gene repression or de repression at an early stage in differentiation will have a wide ranging consequence in restricting the possible fate of the cell.
maternal - Relating to or characteristic of a mother or motherhood; motherly: maternal instinct. Inherited from one's mother: a maternal trait. Related through one's mother: my maternal uncle.