After many extensive molecular investigations of gene families, it has become apparent that a large majority of genes have multiple copies of themselves. This seemingly unnecessary amount of duplicates has led to further research, revealing that these ‘extra’ genes cannot successfully code for proteins (Proudfoot, 1980). These genes were therefore labeled as functionless sequences of DNA, and aptly named pseudogenes. This discovery poses many questions regarding the role and origin of these supposedly non-functional genes, but most importantly what else can we learn from them? Unfortunately, DNA that cannot be expressed into proteins is useless in regards to investigations of the molecular clock (Martin, 1990), however further research proves that we can learn a lot from pseudogenes.
In order to explore what we can learn from pseudogenes, we need to understand them. Firstly, there are two main types of pseudogene, processed and unprocessed. Processed pseudogenes, also known as retropseudogenes, are sequences of transposable DNA that have been reverse transcribed back from mRNA, but have somehow failed to replicate crucial protein coding elements when assimilated back into the genome (Graur and Li, 2000: Skalka and Goff, 1993). Unprocessed pseudogenes can occur by simple replication of a pre-existing pseudogene, or due to adverse point mutations in ‘normal’ functioning genes that can trigger a frame shift in the original protein code. This frame shift can for example, lead to a mixture of premature stop codons and elimination of splicing sites, rendering the gene faulty (Li, Graur and Shuali, 1989).
Initially it was believed that pseudogenes have no purpose, just selfish, parasitic DNA clogging up the genome (Orgel, Crick and ...
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...e4573de165161150&searchtype=a> [Accessed 12th November 2010]
(20) Nishikimi, M. et al. 1994. Cloning and Chromosmal Mapping of the Human Nonfunctional Gene for L-Guluno-y-Lactone Oxidase, the Enzyme for L-Absorbic Acid Biosynthesis Missing in Man*, The Journal of Biological Chemistry, [online] Available at: [Accessed 12th November 2010]
(21) Sakai, H. Itoh, T. Gojobori, T. 2008. Processed Pseudogenes and Their Functional Resurrection in the Human and Mouse Genomes, Wiley: Online Library, [online] Available at: http://onlinelibrary.wiley.com/doi/10.1002/9780470015902.a0021000/abstract> [Accessed 12th November 2010]
Websites
(19) The True.Origin Archive: Exposing the Myth of Evolution.2010. Pseudogenes: Are They Non-Functional? [online] Available at: [Accessed 9th November 2010]
Alu elements are a class of transposable genes found exclusively in the genomic sequences of primates. Averaging in lengths of approximately 300 base pairs, Alu elements are classified as being short interspersed elements, more commonly referred to by the acronym SINEs. These elements interject themselves into the DNA sequence by means of retroposition. Once established into the genome, Alu elements are considered to be stable, only rarely being subjected to deletion. Initial studies on the prevalence of Alu inserts within the modern human genome was calculated to be nearly 5% (Comas, Plaza, Calafell, Sajantila, & Bertranpetit, 2001), however, more recent research indicates that the actual percentage of various Alu elements account for nearly 11% of the DNA sequence (Deininger, 2011). Alu elements are of great importance to scientists, particularly to those who wish to study evolution, as well as, migrational patterns of early human populations.
"Charles Darwin: The Father of Evolution." Darwin1. University of Missouri, n.d. Web. 04 May 2014.
Miller, Kenneth R. and Joseph S. Levine. “Chapter 12: DNA and RNA.” Biology. Upper Saddle River: Pearson Education, Inc., 2002. Print.
The purpose of this experiment was to discover the specificity of the enzyme lactase to a spec...
DNA is the blueprint of life from its creation to its development and until its death. The discovery of the structure of DNA not only revolutionized science and medicine, but it also affected many other facets of existence: evolutionary, industrial, legal, and criminal justice. Its incarnation has benefitted American families and industries and spurred scientific innovation throughout the country. Aptly stated by Francis Crick, “your joys and your sorrows, your memories and your ambitions, your sense of identity and freewill, are in fact no more than the behavior of a vast assembly of nerve cells and their associated molecules. As Lewis Carroll’s Alice might have phrased it: ‘you’re nothing but a pack of neurons.’ [Watson and my] discovery illustrates how that is possible.”
Darwin: A Norton Critical Edition, Second Edition ; ed. by Philip Appleman; copyright 1979, 1970 by W.W. Norton & Company, Inc.
Long standing arguments against the theory of natural selection stem from the occurrence of incipient structures and complex traits in organisms despite the seemingly stochastic nature of mutations. Many complex adaptations observed in nature today are thought to have arisen from less complex ones with simpler functions, therefore these characters are thought to have been “pre-adapted.” In order to go from a simple to a complex structures there must have been a transitional phase, where the two structures function simultaneously or where the new function is assumed without interfering with the old function. These structures are termed incipient or incomplete, and given what we know to be true of natural selection and the theory of evolution it becomes hard to reconcile the idea that natural selection continued to favor these structures despite the lack of selective value. Incipient structures are thought to be neither sufficiently large enough not elaborate enough to perform an adaptive function and thus it also becomes difficult to understand how larger complex characters arise. A discussion of morphological and developmental genetics explains that these structures have been performing useful functions since their simple origins, therefore being selectively favored while at the same time evolving to become large enough to accumulate new more complex functions. Modification of pre-existing genes and regulatory circuits in early development has been extensively studied in metazoans, Hox genes and the development of complex structures such as eyes, limbs and appendages. Phenotypic variation is therefore generated via the modification of existing genes, regulatory processes and developmental processes and this variation is acted o...
...hich inherited traits, such as those for genetic disease, can be tracked over generations. Throughout out the course of human development, scientists will continue to find new new ways to help the human race through the discovery of the human gene inside of each of us, its uses, as well as complications, that can help the survival of our species.
Over the last fifty years or so, scientists have made a great amount of progress in this area, including the development of techniques which allow for the controlled manipulation and replication of specific segments of the human genome. These types of techniques have come to be known as recombinant DNA (rDNA) technology and have allowed scientists to analyze functions of genes which are not necessarily directly expressed at the phenotypic level. This is done by "cutting out" or excising a particular segment of DNA of interest from the genetic material of an individual and inserting it into a bacterial plasmid (a tiny ring of DNA in addition to the normal chromosomal material found within the cells of bacteria).
... starts relaxing the supercoils and altering of DNA and interacts with DNA helicase SGS1 and plays a role in DNA recombination, also cellular aging and maintenance of genome stability. Alternate splicing results in multiple transcript variants. Additional spliced variants of the gene have been described, but their complete length is unknown.
...Glass, Non-coding RNAs as regulators of gene expression and epigenetics, 2011, oxford journals, 90 (3), p430-440
The use of genetic sequencing in the medical field has innumerable possibilities; genomic medicine, as this new field is now called, will enable the human race to make immense advances in understanding how our genetic heredity makes us susceptible to some illnesses and immune to others. The detection of diseases with a high rate of heredity is just one facet of the gem that is genomics; once researchers are able to map out all of the vital components and rare alleles that sometimes play a large factor in disease, it will be possible to target these specific gene combinations, functional elements, and alleles. Because of the fact that protein, produced by our cells’ ribosomes, has an effect on the pathways that help express our inherited traits, it is important that we understand the relationship between DNA and protein, and how this affects the phenotype of an individual’s genetic attributes. For example, sickle-cell anemia is caused by a flaw in one nitrogenous base sequence in DNA. This flaw then translates into RNA, then into amino acids that determine the phenotype that the subject will have. The discrepancy in something as minute as a nitrogenous base and one amino acid makes the difference between a healthy, normal life and a life ...
... to RNA and the translation to proteins, as well as gene expression. Noble does an excellent job of presenting an opposing view to the central dogma of biology, using metaphors to attempt to make his differing views clearer to the reader. While Noble does use a lot of scientific evidence to support his opinions, his use of metaphors is overwhelming and it can easily distract the reader from the point that he is trying to make. ,Nobles’ explanations of gene expression help the reader to understand the process of evolution, giving a more or less clear view as to how redundancy in the genome can lead to variation. Noble neglects, however, to expand upon natural selection or any other ideas related to evolution. If these ideas were present, they were lost somewhere between the overwhelming use of metaphors and the overly detailed explanations of cell signaling processes.
McKinnell, Robert G., and Marie A. Di Berardino. "The Biology of Cloning: History and Rationale."BioScience 49.11 (1999): 875-83. Print
...follows the general code of ethics, but it only has one specific code of ethics for gene synthesis. This worries many people because they cannot see synthetic biologists’ ethical procedures and how these researchers would apply these rules in different situations. In time, there will be an agreed upon code of ethics for synthetic biology and this will help relieve people because they will believe that valuable, but possibly dangerous, information is less likely fall into the wrong hands and that appropriate experimenting occurs. The goal of synthetic biology is to improve medicine and protect the environment. Synthetic biologists want to cure cancer, provide new energy sources, and more sustainable foods. People’s concerns are legitimate and need to be analyzed, but until these ethical concerns and possible risks are addressed synthetic biology cannot move forward.