Genetics & Molecular Biology

Genetically, the Germans and British are very close to each other but the genetic distances between the Swedes and Eastern and Western Finns are larger, and the diversity in these populations is lower. A recent study shows that genetic differences in Central Europe appear smaller than between and even within North European populations.    The study, led by researcher Päivi Lahermo from Institute for Molecular Medicine Finland (FIMM) and University of Helsinki, Finland, and professor Juha Kere from Karolinska Institutet, Sweden. The understanding of genetic variation in human…

Scientists in Cambridge, UK, using a mouse with a human chromosome in its cells, discovered that gene expression, contrary to what was previously thought, is mostly controlled by regulatory DNA sequences. Mice and humans (and most vertebrates) share the majority of their genes but a distinct gene regulation – so, when and where these shared genes become activated – assures their many individual characteristics, and knowledge of this regulation is crucial if we want one day to be able to control gene expression. These new results challenge current belief that gene regulation is mediated by a…

An enigma unique to flowering plants  has been solved, say researchers from the University of Leicester (UK) and POSTECH, South Korea.  Scientists already knew that flowering plants, unlike animals, require not one but two sperm cells for successful fertilization.  Double fertilization is essential for fertility and seed production in flowering plants so increased understanding of the process is important. But the mystery of this ‘double fertilization’ process was how each single pollen grain could produce ‘twin’ sperm cells. One to join with the egg cell to produce the embryo…

Many scientists have documented that over 95% of Human DNA does not have a known purpose. This DNA has been colloquially referred to as "Junk DNA".   Up to 97% of the human genetic information (DNA) is seemingly needless, repetitive "junk" - only about 3% is known to generate proteins, deserving the name "gene". The rest used to be called "junk DNA", lately renamed as "non-coding introns", sometimes labelled by the mysterious, though not very explicit description that these self-similar strands "regulate gene expression".  However, other researchers have not been content to…

Your desires for genome voyeurism, that is. Harvard geneticist George Church has managed to get 10 people to fork over a big chunk of change to have their entire genomes sequenced - that is, the entire thing, not just the SNPs that you get from 23andMe for $400.  Not only did those people pay to have their genomes sequenced, but they agreed to sign away their privacy and expose their naked genomes to the world. Go check it out at www.personalgenomes.org. The NY Times has the backstory.

Scientists in Israel are reporting the first successful spinning of a key natural protein into strong nano-sized fibers about 1/50,000th the width of a human hair. The advance could lead to a new generation of stronger, longer-lasting biocompatible sutures and bandages to treat wounds. The study is scheduled for the November 10 issue of Biomacromolecules. Eyal Zussman and colleagues point out that researchers have tried for years to develop wound repair materials from natural proteins, hoping that such fibers would be more compatible with body tissue than existing materials. Scientists…

As many readers here know, evolution isn't just some esoteric topic disconnected from the rest of biology. It's a core theory that is underlies all of biology. Today our department heard a talk from Dr. Sudhir Kumar, a U of Arizona Arizona State University scientist who is using evolutionary theory to improve our ability to predict which mutations are likely to cause disease (PDF). The problem is this: it's becoming cheaper for any of us to go out and get ourselves genotyped. Companies like 23andMe, deCODEme, and Navigenics will give you a read out of your DNA at hundreds of thousands of…

The means by which proteins provide a 'border control' service, allowing cells to take up chemicals and substances from their surroundings, whilst keeping others out, is revealed in unprecedented molecular detail for the first time in Science Express. The scientists behind the new study have visualised the structure of a protein called Microbacterium hydantoin permease, or 'Mhp1', which lives in the oily membrane that surrounds bacteria cells. It belongs to a group of proteins known as 'transporters' which help cells take up certain substances from the environment around them. This is the…

When it comes to embryo formation in the lowly fruit fly, a little molecular messiness actually leads to enhanced developmental precision, according to a study in the Oct. 14 Developmental Cell from Cincinnati Children's Hospital Medical Center. While the fundamentals of this tiny bug's reproductive biology may seem insignificant, one day they could matter quite a bit to humans. That's because the study provides new information about how cells choose their own fates, especially in maintaining the size relationship and proportionality of body parts during embryonic development, said Jun Ma, Ph…

Scientists at Bonn and Düsseldorf Universities investigated over 500,000 positions in the human genome and found a gene variant which occurs clearly more frequently in bald men than in control persons. This means they have found a new hair loss gene, according to their study in Nature Genetics. In 2005, these scientists had already characterized the first hair-loss gene inherited through the maternal line, which explained why hair-loss in men often reflects that of their maternal grandfathers. This newly discovered gene, on the other hand, may now account for the similarity in cranial hair…