Genetics
Rheumatoid arthritis and the impact of genetic factors on mortality
|
|
Study associates DRB1 shared epitope genotypes with increased risk of death from heart disease or cancer in rheumatoid arthritis patients
A chronic autoimmune disease, rheumatoid arthritis (RA) is marked by inflammation that takes a progressive toll on not only the joints, but also various organs and the whole body. RA sufferers, as many studies have shown, tend to face a high risk for early death, increasing with the severity of their symptoms. The most prevalent cause of death among RA patients is cardiovascular disease. As in the general population, classic factors such as age, hypertension, diabetes, and smoking have been implicated in the RA death rate. Little is known, however, about the specific influence of genetic factors on mortality.
Crohn’s disease has strong genetic link
|
|
Scientists have identified a handful of genes that increase the risk of developing Crohn’s disease, confirming that the often debilitating inflammatory bowel disease has a strong genetic component.
U.S. and Canadian researchers scanned the entire genome—all 22,000 genes—of about 6,000 people. Approximately half had Crohn’s disease and half did not, they reported in the medical journal Nature Genetics.
Major genetic study identifies clearest link yet to obesity risk
|
|
Scientists have identified the most clear genetic link yet to obesity in the general population as part of a major study of diseases funded by the Wellcome Trust, the UK’s largest medical research charity. People with two copies of a particular gene variant have a 70% higher risk of being obese than those with no copies.
Obesity is a major cause of disease, associated with an increased risk of type 2 diabetes, heart disease and cancer. It is typically measured using body mass index (BMI). As a result of reduced physical activity and increased food consumption, the prevalence of obesity is increasing worldwide. According to the 2001 Health Survey for England, over a fifth of males and a similar proportion of females aged 16 and over in England were classified as obese. Half of men and a third of women were classified as overweight.
Gene Test Shown to Measure Heart Function After Transplant
|
|
New research suggests a genomic test may provide detailed information on how well a transplanted heart is performing. The gene expression profiling (GEP) test, known as the Allomap® test, is currently used to detect the absence of heart transplant rejection instead of routine invasive heart muscle biopsies, but has now been shown to correlate with oxygen saturation levels, the pressure in the heart before pumping, and the electrical properties of the transplanted heart. These measures are crucial to understanding how well the transplanted heart is functioning.
The research will be presented on Tues., March 27, at the American College of Cardiology’s 56th Annual Scientific Session in New Orleans by Martin Cadeiras, M.D., postdoctoral research fellow in the lab of Mario Deng, M.D., director of cardiac transplantation research and associate professor of clinical medicine at Columbia University College of Physicians and Surgeons, and cardiologist at NewYork-Presbyterian Hospital/Columbia University Medical Center. The presentation is based on preliminary data on 80 patients who received the GEP test. Physicians hope to confirm these results in future studies.
Newborns with respiratory distress potentially have rare genetic disease
|
|
Newborns with respiratory distress should be evaluated for primary ciliary dyskinesia, a rare genetic disease that has features similar to cystic fibrosis, says Thomas Ferkol, M.D., from Washington University School of Medicine in St. Louis. He reports finding that about 80 percent of patients with primary ciliary dyskinesia (PCD) have a history of newborn respiratory distress.
“The diagnosis of PCD requires a high index of suspicion, but PCD must be considered in any term newborn who develops respiratory distress or persistent hypoxemia (low oxygen in the blood), especially those who have reversed internal organs or an affected sibling,” says Ferkol, director of the Division of Pediatric Allergy and Pulmonary Medicine at Washington University School of Medicine and St. Louis Children’s Hospital.
International study points to new breast cancer-susceptibility gene
|
|
A gene whose existence was detected only a couple of years ago may increase women’s risk of breast cancer when inherited in a mutated form, and may contribute to prostate cancer as well, researchers at Dana-Farber Cancer Institute and colleagues in Finland report in a new study.
The gene, known as PALB2, may play a role in only about 1 percent of breast cancer cases in the select population that was studied (Finnish women), but its discovery sheds light on the complex web of gene interactions that underlies the disease, say the authors of the study, which is being published by the journal Nature on its Web site, http://www.nature.com/nature, and later in a print edition.
Down’s syndrome test eliminates miscarriage risk
|
|
A new non-invasive test that examines fetal DNA can pick up genetic abnormalities such as Down’s syndrome and, unlike more intrusive tests that may raise the risk of miscarriage, the new diagnostic tool developed by the US company Ravgen poses no threat to the mother or fetus.
The test uses fetal DNA extracted from blood samples taken from the mother to screen for chromosomal abnormalities, researchers explained. In a preliminary study of 60 pregnant women reported online by The Lancet medical journal the test produced promising results.
Major Link in Brain-Obesity Puzzle Found
|
|
A single protein in brain cells may act as a linchpin in the body’s weight-regulating system, playing a key role in the flurry of signals that govern fat storage, sugar use, energy balance and weight, University of Michigan Medical School researchers report.
And although it’s far too early to say how this protein could be useful in new strategies to fight the world’s epidemic of obesity, the finding gives scientists an important system to target in future research and the development of anti-obesity medications.
In the February issue of the Journal of Clinical Investigation, U-M researcher Liangyou Rui, Ph.D. and his team report their findings on a protein called SH2B1, and specifically on its activity in brain cells.
Genetic variation may reduce Alzheimer’s risk
|
|
Adults with a genetic variation enabling them to express higher levels of fetal hemoglobin may have a reduced risk of Alzheimer’s disease, researchers say.
A study of 209 families with at least two siblings with Alzheimer’s and one unaffected sibling showed that those with this genetic variation are less likely to have the disease, researchers say in Neurobiology of Aging. An estimated 25 percent of the population has the XmnI polymorphism.
Genetic Mechanism Helps Explain Chronic Pain Disorders
|
|
Researchers at the University of North Carolina at Chapel Hill have discovered that commonly occurring variations of a gene trigger a domino effect in chronic pain disorders. The finding might lead to more effective treatments for temporomandibular joint disorder (TMJD) and other chronic pain conditions.
Catechol-O-methyltransferase (COMT), an enzyme that metabolizes neurotransmitters such as epinephrine, norepinephrine and dopamine and that has been implicated in the modulation of persistent pain, as well as cognition and mood, is regulated by a gene, also called COMT. Previous UNC-led research showed that common genetic variants of this gene are associated with increased pain sensitivity and the likelihood of developing TMJD.
Development of gene therapy
|
|
Since the late 1980s, gene therapy, more than virtually any other type of therapy, has given rise not only to high expectations of treatment success but also great concerns regarding health risks. Since the Deutsche Forschungsgemeinschaft (German Research Foundation, DFG) issued its first memorandum in 1995, this field of research has developed enormously. Wide-ranging experiments have shown the therapeutic potential as well as the risks of gene therapy. The second memorandum, which has just been presented by the DFG Senate Commission on Genetic Research, makes it clear that gene therapy already shows signs of success in certain areas, such as severe hereditary immunodeficiency diseases, while in other areas there is still considerable need for research. Moreover, the clinical application of gene therapy requires careful risk/benefit assessment, although in this respect it does not differ substantially from other therapeutic approaches.
Gene Therapy Shows Promise Against Hereditary Lung Disease
|
|
An experimental gene therapy to combat alpha-1 antitrypsin deficiency, a common hereditary disorder that causes lung and liver disease, has caused no harmful effects in patients and shows signs of being effective, University of Florida researchers say.
In a clinical trial, researchers evaluated the safety of using a so-called gene vector - in this case an adeno-associated virus - to deliver a corrective gene to 12 patients who are unable to produce a protein essential for health called alpha-1 antitrypsin.
Genetics a key factor in premature infants’ devastating eye disease
|
|
Genetics play a major role in predisposing infants to retinopathy of prematurity (ROP), a disease prevalent in premature infants that disrupts normal blood vessel development of the retina and can lead to blindness, researchers at Yale School of Medicine report in the November issue of Pediatrics.
“This is the first definitive study to show that genetic factors are a significant component of ROP, and to quantify the extent of that genetic contribution,” said lead author Vineet Bhandari, M.D., assistant professor of pediatrics at Yale School of Medicine.
Possible key human evolution genes identified
|
|
They could be the missing links of human genetic evolution - areas of human DNA that changed dramatically after the evolutionary division from chimpanzees, though they had remained almost unchanged for millennia before.
Scientists from the United States, Belgium and France identified 49 “human accelerated regions” (HARs) showing a lot of genetic activity.
In the most active, identified as HAR1, they found 18 out of the 118 nucleotides had changed since evolutionary separation from chimps some 6 million years ago, while only two had changed in the 310 million years separating the evolutionary lines of chimps and chickens.
Different genes may be responsible for causing autism in boys than in girls
|
|
Like detectives trying to solve a murder case, researchers searching for the biological cause of autism have come up with some surprising suspects.
They’ve found that different genes may be responsible for causing autism in boys than in girls.
In addition, the researchers also have discovered that other genes may play a role in the early onset form of the developmental disorder and in the recently verified regression, or late onset, type of autism, according to a new study published today in the online edition of the journal Molecular Genetics.
