Genetics & Molecular Biology

Not all enzymes that are assumed to require an RNA component in order to function do actually contain RNA, according to a study  that focused on the enzyme RNase P.   Contrary to accepted scientific theory, the project team from Vienna has long believed that certain forms of RNase P do not contain any RNA. They say they have now succeeded in proving their point through a series of experiments and the results are published today in the journal CELL. Although ribozymes are not quite living fossils, these enzymes, which function only in the presence of RNA, hail from a long gone age…

A group of researchers have created a  biodegradable 'scaffold' and living heart cells or stem cells seeded onto such a scaffold could develop into a patch of cardiac tissue  to treat congenital heart defects, or aid the recovery of tissue damaged by a heart attack. The biodegradable scaffold would be gradually absorbed into the body, leaving behind new tissue. The accordion-like honeycomb scaffold, to be reported in the Nov. 2 online edition of Nature Materials, is the first to be explicitly designed to match the structural and mechanical properties of native heart tissue. As a…

The 5,300 year old human mummy dubbed Öetzi (or ‘the Tyrolean Iceman’)  is highly unlikely to have modern day relatives, according to new research published today by a team of scientists from Italy and the UK. They have sequenced Öetzi’s entire mitochondrial DNA (mtDNA) genome, which is passed down through the maternal line, and found that he belonged to a genetic lineage that is either extremely rare or has died out. The research has generated the oldest complete Homo sapiens mtDNA genome to date, and overturns previous research conducted in 1994 on a small section of Öetzi’s mtDNA,…

Researchers have defined a mutation in the mouse genome that mimics progressive hearing loss in humans. A team from the Wellcome Trust Sanger Institute in Cambridge, UK, working with colleagues in Munich and Padua, found that mice carrying a mutation called Oblivion displayed problems with the function of hair cells in the inner ear, occurring before clear physical effects are seen. The study is published October 31 in PLoS Genetics. Progressive loss of hearing affects around six out of ten people over the age of 70. Whilst environmental causes can contribute, genetic influences also play a…

In the aftermath of the Palin fruit fly comment, some bloggers are knocking people for not knowing that the model organism D. melanogaster is technically not a fruit fly. But the fact is that the confusing nomenclature isn't some recent mix-up - as we see in the paper everyone's citing, biology textbooks as early as 1923 have referred to Drosophila as fruit flies, and Among 13 textbooks published after 1945, with one exception all use fruit fly as the common name... Noteworthy is the finding that even the Entomological Society of America has been seduced. Its list of common names of insects…

Scientists have expressed genes from snapdragon in tomatoes to grow purple tomatoes high in health-protecting anthocyanins.  Anthocyanins are naturally occurring pigments found at particularly high levels in berries such as blackberry, cranberry and chokeberry. Scientists are investigating ways to increase the levels of health-promoting compounds in more commonly eaten fruits and vegetables. Anthocyanins offer protection against certain cancers, cardiovascular disease and age-related degenerative diseases. There is evidence that anthocyanins also have anti-inflammatory activity, promote…

The political fray has entered into the world of genetics, and as usual, our politicians have no real idea what they are talking about. In an October 24th speech about children with special needs, Sarah Palin, the Republican nominee for Vice-President, made the following statement about funding forIDEA, or the Individuals with Disabilities Education Act. “This is a matter of how we prioritize the money that we spend. We've got a three trillion dollar budget, and Congress spends some 18 billion dollars a year on earmarks for political pet projects. That's more than the shortfall to fully fund…

Since Palin's comments on fruit fly research are getting some commentary, it's a good time to review the value of model organisms in basic research. One of the things budding geneticists, biochemists and cell biologists learn very quickly when they enter grad school is that studying humans is usually not the best way to successfully tackle the most interesting research questions. You can ask questions about human biology, but to answer them you generally turn to an elite club sometimes called the Security Council of biology: the bedrock group of five model organisms. Fruit flies, baker's…

I have complained recently about the state of basic research support in Canada, as the current government is pushing for more short-sighted, applied, industry-oriented work. This is as nothing compared to the attitude of some politicians south of the 49th. Here is how a recent paper of mine began*: Through all the major transitions in genetics over the past 100 years – from early mutation and mapping studies involving countless crosses and phenotypic analyses, to karyotyping and polytene chromosome banding, to the application of allozymes in population-level surveys, to the advent of complete…

Clubfoot, one of the most common birth defects, has long been thought to have a genetic component. Now, researchers at Washington University School of Medicine in St. Louis report they have found the first gene linked to clubfoot in humans. By studying a multi-generation family with clubfoot, the scientists traced the condition to a mutation in a gene critical for early development of lower limbs called PITX1. While other genes are also likely to be linked to clubfoot, the new finding is a first step toward improved genetic counseling and the development of novel therapies. "To our knowledge…