Genetics & Molecular Biology
Genes that contain instructions for making proteins make up less than 2% of the human genome. Yet, for unknown reasons, most of our genome is transcribed into RNA.
Investigating all transcripts produced in a yeast cell, researchers in the groups of Lars Steinmetz at the European Molecular Biology Laboratory (EMBL) in Heidelberg, Germany, and Wolfgang Huber at the European Bioinformatics Institute (EMBL-EBI) in Hinxton, UK found that most regions of the yeast genome produce several transcripts starting at the same promoter. These transcripts are interleaved and overlapping on the DNA. In contrast to what was previously thought, the vast majority of promoters seem to initiate transcription in both directions.
Ever since the time of Mendel, students and the general public have struggled with how to understand the interconnection of mathematics and genetics. Not because understanding Mendelian mathematics is a difficult subject, but rather because the application of mathematics has never been the strong suit for most people.
Reginald Punnett recognized this struggle when in 1909 he introduced the Punnett square - the cornerstone of genetics education in almost every classroom. In fact, for almost 100 years now, while the science of genetics has evolved by leaps and bounds, little has changed in the way that educators teach genetics.
A research team in Portugal and the US has found for the first time nicotine receptors in the taste buds. In fact, although most of the toxicity of smoking is linked to other components, it is nicotine that leads to smoking addiction and until now it was believed that this substance had to migrate into the brain to bind its specific receptors and provoke its effects.
Daniel at Genetic Future has posted the latest edition of Gene Genie
. Go read about blog reactions to Steven Pinker's genome, a DNA database for Portuguese criminals, predictions on what super-power-conferring mutations George Church might find in the genomes of his first 10 volunteers for the Personal Genome Project, how DNA can tell us where medieval scholars got their cows to make cow-hide manuscripts, and much, much more.
It's a great edition of Gene Genie, so go pay Daniel a visit.
Scientists who study how human chemistry can permanently turn off genes have typically focused on small islands of DNA believed to contain most of the chemical alterations involved in those switches. But after an epic tour of so-called DNA methylation sites across the human genome in normal and cancer cells, Johns Hopkins scientists have found that the vast majority of the sites aren’t grouped in those islands at all, but on nearby regions that they’ve named “shores.”
Scientists at deCODE genetics have completed the largest study of ancient DNA from a single population ever undertaken. Analyzing mitochondrial DNA, which is passed from mother to offspring, from 68 skeletal remains, the study provides a detailed look at how a contemporary population differs from that of its ancestors.
The results confirm previous deCODE work that used genetics to test the history of Iceland as recorded in the sagas. These studies demonstrated that the country seems to have been settled by men from Scandinavia – the vikings – but that the majority of the original female inhabitants were from the coastal regions of Scotland and Ireland, areas that regularly suffered raids by vikings in the years around the settlement of Iceland 1100 years ago.
The pharmaceutical industry is currently facing some key challenges, like an increase in drug development costs, a decrease in the number of drugs being approved and scrutiny from regulatory authorities. Patients themselves are also demanding more effective and safer drugs.
Pharmacogenomics says they can help to guide drug development and therapy by correlating gene expression with a drug's efficacy.
Forsyth Institute scientist Peter Jezewski, DDS, Ph.D., says that duplication and diversification of protein regions ('modules') within ancient master control genes is key to the understanding of certain birth disorders. Tracing the history of these changes within the proteins coded by the Msx gene family over the past 600 million years has also provided additional evidence for the ancient origin of the human mouth.
Harvard psychologist Steven Pinker's genome is being sequenced as part of the Personal Genome Project
, and he's been gazing at the results, attempting to divine some meaning in the A''s, T's, G's and C's. He shares his musings in a Sunday Times Magazine
essay that captures both the excitement of personal genomics and its pitfalls.Personal Genomics and Disease
How did life begin? A pair of Scripps Research Institute scientists say they have taken a significant step toward answering that question because they have synthesized RNA enzymes that can replicate themselves without the help of any proteins or other cellular components - and the process proceeds indefinitely.