Tuesday, May 26, 2009

Linking Changes in DNA to Health Problems

New tool helps researchers identify DNA patterns of cancer, genetic disorders discusses a new means of identifying minute changes in DNA patterns that lead to medical disorders. Quoting from the linked article:

David Cox, a Ph.D. student in computer science at NC State, devised the "symbolic scatter plot" tool to provide a visual representation of a DNA sequence. Cox explains, "The human visual system is more adept at identifying patterns, and differentiating between patterns, than existing computer programs such as those that try to identify repetitions of DNA sequences." In other words, the naked eye sees patterns better than computers can.

Identifying patterns in a sequence of DNA is important because it can help researchers identify the minute genetic variations between subjects that suffer from a disease, such as cancer, and subjects that do not. "Improved identification of relevant DNA sequences will hopefully expedite the development of successful treatment for a range of diseases," Cox says, "by allowing researchers to focus on the components of DNA that are related to the disease and improving our understanding of the genetic mechanisms of these diseases. For example, what turns specific genes on and off?"


Sunday, May 24, 2009

Dumbing Down the American Electorate

Viewpoint has an entry that is both funny and troublesome. It is titled God Help Us and cites some anecdotal stories from the most recent presidential election as derived from a piece in First Things. Here they are:

During the campaign, a woman in her mid-twenties told me she would not vote for Gov. Sarah Palin because "Palin is so stupid she doesn't even know where Alaska is." I asked what she meant, and she explained that in a TV interview Palin had referred to Alaska as "up North," whereas everyone knows Alaska is "down there with Hawaii south of California." I surmised that her knowledge of geography is based on seeing textbooks depicting the U.S. map with an insert for Alaska and Hawaii placed in the lower left-hand corner, underneath California. When I gently explained where Alaska is, she dismissed it with, "Well, Palin's stupid anyway."

Too funny. But pathetic as well.

A second voter, a man about thirty, said he would vote for Obama rather than McCain because "Obama has young children so he probably cares more about the future than McCain does."

You cease caring about the future when your kids become adults? Brilliant.

A Catholic nun was enthusiastically supporting Obama (as was most of her order), and, when I pointed out Obama's positions on abortion issues, she refused to believe it was true on the grounds that such a wonderful man could not possibly support abortion.

The brain ceases to function and touchy feely takes over.


Monday, May 18, 2009

DNA Helicases

In prepararing to analyze a research paper I'll begin posting a series of blog entries that provide mini-tutorials about molecular biological constructs. I'll then link to them in a larger blog entry. This one is focused on DNA helicases. As this link suggests, DNA helicases play a role in the unwinding of DNA which occurs during essential cellular functions like replication, recombination, repair and transcription.

For an easy to read and informative abstract try Unwinding of Unnatural Substrates by a DNA Helicase. Its authors are Alan J. Tackett, Patrick D. Morris, Regina Dennis, Thomas E. Goodwin, and Kevin D. Raney.


Monday, May 11, 2009

Cell Cycle Arrest and DNA Repair

There is an article in the jounal Nature (Volume 459 Number 7243) titled F-box protein FBXO31 mediates cyclin D1 degradation to induce G1 arrest after DNA damage. It was authored by Manas K. Santra, Narendra Wajapeyee and Michael R. Green.

When DNA is damaged in eukaryotic cells a signaling pathway called the DNA damage response (DDR) becomes an essential part of the cellular coping response. Affected cells need to regulate their cell cycle so that DNA repair can be coordinated with the progression of the cycle. DDR coordinates adjustments in the cycle progression.

Researchers studied the function of a protein known as FBXO31. When this protein is expressed it facilitates the degradation of cyclin D1. Cyclin D1 plays a role in regulating the progression of the cell cycle from G1 to the S phase. It helps maintain the G1 phase. An increase in FBXO31 levels has been observed with the incidence of different types of DNA damaging agents.