Aurora magazine

The zebrafish is extremely prolific: the female produces an average of 200 eggs a week. Embryos are transparent and develop rapidly within 2-3 months.
The biological mechanisms of the embryonic growth of Danio rerio resemble many aspects to human beings. For these reasons and for the ease with which researchers succeed in inducing mutations in their DNA, zebrafish has been chosen as a genetic model for the study of diseases and defects in human development.

By analyzing the interactions between fish genes, experts hope to shed light on the regulatory mechanisms of gene expression in human DNA.
Dozens of research centers around the world have specialized in zebra fisheries over the last few years and the competition between Europe and the United States in this area is very strong, both purely scientific and from the point of view of 'Pharmaceutical and biotechnology industry.

The ZF-MODELS project

The objective of the European Commission and the Swiss National Fund for Scientific Research is to support the competitive effort of the old continent.
This is how the ZF-MODELS project, which was launched in January and coordinated by the Max Planck Institute in Tübingen, was attended by fifteen research institutes in France, Germany, Great Britain, Italy, Norway, the Netherlands and Switzerland with a Politecnico Zurich. The European Commission will contribute to the total cost of the initiative with twelve million euros, the Swiss Fund with another 400,000 euros.

The most modern techniques of DNA manipulation and analysis will be applied massively: researchers will produce thousands of mutant fish to study the effects of mutations, determine the function of each gene, and correlate the interactions between them.

All the information gathered within the project will come together in anatomical and genetic zebrafish atlas that will be available free of charge to the scientific community and the public interested on the zf-models site.

The zebrafish in Zurich

The Zurich Politecnico research group taking part in the ZF-MODELS project, led by the neurobiologist Stephan Neuhaus, has long been using zebrafish as a model for embryonic development analysis. "Our specific field of interest is the development of the visual apparatus," explains Neuhaus, "in practice we produce and analyze genetic mutations that involve visual impairment."

The Swiss neurobiologist and his team have developed techniques to detect blind larvae. "Let's investigate the causes of the blindness of these mutated specimens," says Neuhaus, "and identify the molecular defects at the origin of visual apparatus malfunction."

Some of the mutations have similarities with hereditary human diseases, such as retinal dystrophy. "We therefore hope that our work will be useful in the medical field."

Sardinia is a rare treasure for geneticists worldwide. These include the Institute of Biomedical and genetic research scientists of the National Research Council (CNR-IRGB), who sequenced the RNA of 600 Sardinians. On the island there are in fact rare genetic variants, which allow you to better understand how the human genome functional.

Professor Francesco Cucca and his team are authors of a study that lasted six years, which analyzed RNA and DNA of 600 Sardinian subjects. Thanks to statistical models, scientists have linked the DNA and RNA of nucleated blood cells. In this way they identified thousands of previously unknown genetic variants, that influence the risk of genetic diseases. The findings shed new light on understanding the human genome, with possible implications for the prevention of hereditary diseases.
Before starting with the middle phase of the study, the researchers had to choose which type of RNA sequence. They are so focused on what polyadenylated, very important in the production of proteins. The polyadenylated RNA also includes other important regulators RNA, allowing a large sequencing and accurately.

The dell'Irgb-Cnr study is neither the first nor the last Sardinian focused on genes. Sardinia The project has been running since 2001 and aims to study how genetic variables influencing parameters of biomedical relevance. Sardinia enjoys local partnerships, such as with CRS4, and international.

Source: healthdesk.it

Age is one of the factors that influence the capacity to procreate. Researchers at the University of Montreal Hospital Research Center (CRCHUM) examined the genetic bases connected to this problem in women. They have thus found a new possible explanation.

The oocytes are the female reproductive cells before being fertilized and develop into ova. Women have a specific number, which over the years goes down. As the body ages, moreover, the quality of the remaining eggs diminishes. All this makes it much harder natural conception after 37 years of age.

Canadian researchers examined the genetic causes of oocyte cell. They identified errors in chromosome segregation, splitting pairs of alleles during the formation of germ cells. Errors cause oocytes with abnormal numbers of chromosomes, resulting in difficulty in conceiving.

The most likely explanation for the increase of chromosomal abnormalities is a malfunction of cohesin. It is a protein complex that holds together the chromosomes. According to many scholars, with age the cohesin deteriorates and the chromosomes lose cohesion. Canadian researchers have expanded this theory.

Microtubules are cylindrical structures internal to the cells, responsible for cell movement. When the cell prepares for division, the chromosomes unite around the helical structure and select them. After the division, they send the chromosomes to opposite ends of the nucleus of the daughter cells, precisely causing segregation.

The Canadian study shows that 50% of the eggs of older mice have dysfunctional microtubules. The problem therefore is not the age of the core, as that of the oocyte in its entirety. By placing a young nucleus into an oocyte old, in fact, the problems remain. The finding also applies to human women and could open the door to new methods to rejuvenate the eggs. During pregnancy it is important to undergo controls and prenatal screening tests: with such fetal DNA test, the mother can know if the fetus is affected by chromosomal abnormalities.

Source: medicalnewstoday.com

Malignant brain gliomas account for 40% of cases of brain tumors. They are common, especially among older adults and affects glial cells. These cells support the central nervous system and produce myelin, the coating of the nerves.

The tumor grows in both diffusive manner along the fiber bundles, both in proliferative manner. In the latter case, the glioma form of the masses who make pressure on the brain. This causes seizures, motor and cognitive deficits difficulties. The changes that disappear sometimes completely with taking anti-edemigeni drugs such as cortisone. It is, however, a purely symptomatic treatment. Surgery is currently the best way to control the spread of the tumor.

In 60% of cases, gliomas occur with seizures or difficulty concentrating and memory. It then proceeds with a brain CT scan and an MRI, which show the masses surrounded by edema. In the case where the diagnosis is in doubt, it proceeds with a total body CT scan with contrast fluid. This will exclude other types of metastatic cancer.

For now, the treatment includes combination of surgery, radiation and chemotherapy. It removes the tumor and reduces the pressure on the brain, thereby improving symptoms. In this way the patient is able to maintain at least part of its functional integrity. Current treatments, however, suffer from the lack of knowledge that you have cancer. It is known that gliomas grow from mutated stem cells, which multiply in an uncontrolled manner and form the tumor mass. It is unclear why this phenomenon.