BIO.7.C

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The student is expected to identify and illustrate changes in DNA and evaluate the significance of these changes; and
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Knowledge and Skills Statement

Science concepts--mechanisms of genetics. The student knows the role of nucleic acid in gene expression.

Examples of gene mutations include point mutations, which are mutations to a single nucleotide base such as insertions, deletions, and substitutions. Insertions and deletions can be caused by a single nucleotide or a section of bases. They have a cascading effect causing a shift in the reading frame and are known as a frameshift mutation.

A substitution of one amino acid for another may affect the overall protein structure, and the enzyme produced may have a change in function. Truncating the protein early produces an incomplete and nonfunctional protein. Frameshifts in the DNA sequence make the code illegible, and if it makes a protein at all, the protein does not function as originally intended.

a polynucleotide (nucleic acid) found in most organisms as the genetic material; composed of a specific combination of monomers of nucleic acid, the combination of which determines the genetic sequence of organisms; made up of a sugar (deoxyribose), a phosphate, and a nucleic acid (one of Adenosine, Thiamine, Guanine, and Cytosine)

describes how certain proteins are manufactured according to a recipe found within the DNA; the mechanism by which certain genes are turned on, up, down, or off, resulting in variations in the amount of product they produce

long-chain polymeric biomolecule; main information-carrying molecule of the cell; determines the inherited characteristics of every living thing

Research

Gonzalez, Beatriz Y., and Johannes H. van Oostrom. "Favorite Demonstration: Using Dice to Explore the Consequences of DNA Mutations." Journal of College Science Teaching 38, no. 5 (May-June 2009): 56-59. https://www.proquest.com/docview/200327345?pq-origsite=gscholar&fromopenview=true&sourcetype=Scholarly%20Journals

Summary:  Working collaboratively, students explore the effect of different types of DNA mutations using dice. The exercise provides students with a tangible way of visualizing how mutations may contribute to genetic diversity and the randomness with which they may occur. After the exercise, students comprehend better why some mutations may cause devastating phenotypic effects, while others do not affect the resulting protein.

Research

Stenson, Peter D., Edward V Ball, Katy Howells, Andrew D Phillips, Matthew Mort, and David N Cooper. "The Human Gene Mutation Database: Providing a Comprehensive Central Mutation Database for Molecular Diagnostics and Personalised Genomics." Human Genomics 4, no. 1 (December 2009): 69-72. https//:doi.10.1186/1479-7364-4-2-69.

Summary:  HGMD Professional remains the only comprehensive database of germline mutations in nuclear genes underlying or associated with human inherited disease. It can be used to search for newly identified gene lesions to determine whether or not they are novel. It can be searched on a gene-wise basis to obtain an overview of the known mutational spectrum for a given gene (via a dynamic mutation viewer which depicts coding region mutations superimposed on the cDNA sequence of a gene). It can also be searched for other examples of a specific type of mutation in a specific location (e.g. at position +5 to a donor splice site) to garner evidence for the pathological authenticity of a given lesion.