(Press-News.org) Scientists at the Wellcome Trust Centre for Human Genetics, University of Oxford, have identified a genetic variant which influences whether a person with dyslexia is more skilled with either the left or right hand. The finding identifies a novel gene for handedness and provides the first genetic evidence to support a much speculated link between handedness and a language-related disorder.
The majority of people worldwide are right-handed. Since the left side of the brain controls the right side of the body, and vice versa, this implies that for most people the left hemisphere of the brain is the dominant side for motor functions. It is also known from family studies that genetics strongly influences handedness.
Most individuals also have left-hemisphere dominance for language function, as demonstrated by language impairment in individuals with damage to certain regions of the left side of their brain.
It has since been suggested that the population bias towards right-handedness evolved as a consequence of the evolution of language. Therefore, scientists have thought that there may be a link between hand preference and disorders that affect language development, such as autism and specific language impairment (SLI). However, no convincing evidence has been found.
In a study funded by the Wellcome Trust, the Medical Research Council and the European Union, scientists scanned the genomes of 192 children with reading difficulties. These children also had their left and right hand skill measured. The results of the study are published online today in the journal Human Molecular Genetics.
The scientists found a strong link between a variant of a gene called PCSK6 and relative hand skill in these children with reading difficulties. Specifically, while most people are better at using their right hand, those who carried the variant in PCSK6 were, on average, more skilled with their right hand compared to the left than those not carrying the variant. This result was also seen in two independent groups of children with reading difficulties.
The protein product of the gene PCSK6 is known to interact with another protein called NODAL. Previous experiments have shown that NODAL plays a key role in establishing left-right asymmetry early in embryonic development. This suggests that genetic variants of PCSK6 may have an effect on the initial left-right patterning of the embryo that in turn influences the development of brain asymmetry, and thus handedness.
Furthermore, as William Brandler, one of the study's authors explains: "Our closest relatives, the great apes, do not display the striking bias towards right-handedness seen in humans. So understanding the genetic basis of handedness may offer us significant insights into our evolution."
"This study provides the first genetic link between handedness, brain asymmetry and reading ability," says Professor Tony Monaco, leader of the group that made this discovery. "Despite the known biological function of PCSK6, this is the first study implicating it with handedness. The fact that this association also seems to be apparent in people with dyslexia provides an interesting clue to explore whether there is a link between handedness and language-related disorders."
One of the aims of this study was to understand the genetics of handedness, and the results should open up new avenues into exploring the biology of language-related disorders, and help identify whether the evolution of language and handedness did indeed go hand-in-hand.
INFORMATION: END
WASHINGTON, DC: A new report from the Project on Emerging Nanotechnologies (PEN) at the Woodrow Wilson International Center for Scholars explores a variety of voluntary options available for the oversight of nanotechnology products and processes. The report, Voluntary Initiatives, Regulation, and Nanotechnology Oversight: Charting a Path, by Dr. Daniel Fiorino, Director of the Center for Environmental Policy at American University, provides a historical overview of voluntary approaches to environmental protection and assesses their applicability to the emerging field of ...
Laparoscopic or 'keyhole' surgery is a safe, effective way of removing bowel tumours and should be offered to all patients undergoing surgery for colorectal cancer, according to researchers from the University of Leeds.
Patients who have laparoscopic surgery spend less time in hospital and recover more quickly from the operation. Now long-term follow-up data has confirmed that this way of doing surgery does not make patients with colorectal cancer more vulnerable to the disease returning, as some had feared. And overall survival rates for keyhole surgery are just the ...
Synopsis: A patient with a long head biceps (LHB) tendinopathy, which is a pain and/or tearing of the tendon, may also have a shoulder problem and/or a rotator cuff tear. LHB tendinopahy can be caused by injury, trauma, overuse, inflammation or degeneration. Because of the variety of the causes and the range of possible severity, a patient needs a thorough examination, including radiographic imaging to determine the diagnosis and treatment. Traditional treatments include both surgical and nonsurgical approaches.
"The surgeon's goal in treating any long head biceps tendinopathy ...
Was it the evolution of the hand, or of the brain, that enabled prehistoric toolmakers to make the leap from striking off simple flakes of rock to fashioning a sophisticated hand axe?
A new study finds that the ability to plan complex tasks was key. The research, published Nov. 3 in the Public Library of Science journal PLoS ONE, is the first to use a cyber data glove to precisely measure the hand movements of stone tool making, and compare the results to brain activation. (Video: http://tinyurl.com/2w9cd4d)
"Making a hand axe appears to require higher-order cognition ...
Shopping was the next most popular answer in the survey, carried out last month by researchers from Nottingham University Business School.
On a scale of zero to 10, Robin scored an average of 8.2 for visitors and 8.6 for locals in terms of the importance of his links to the city — and most agreed he was a "hero".
Yet tourism experts say neither Nottinghamshire nor Yorkshire, which stakes a rival claim to the legend, has made the most of Robin — despite fighting over his origins.
In fact, five years ago Nottingham infamously ditched him from its branding in favour ...
According to a new study from the Journal of Bone and Joint Surgery (JBJS), patients with acute plantar fasciitis who perform manual plantar fasciitis stretching exercises, as opposed to shockwave therapy, had superior results and higher patient satisfaction.
Study details and findings:
A total of 102 patients who had acute plantar fasciitis pain, were randomly assigned to two groups. Acute is defined as any patient that experiences pain for less than six weeks. 54 people performed an eight-week stretching program, while 48 people received repetitive low-energy radial ...
Vomiting is unpleasant. Nearly 30% of all patients suffer from nausea and vomiting after surgery. The financial repercussions of this are longer patient stays in the recovery room, with increased need for personnel. Appropriate prophylaxis and treatment can prevent postoperative nausea and vomiting. In a systematic review of the literature, Dirk Rüsch and co-authors investigate how treatment recommendations for nausea after general anesthesia can be improved (Dtsch Arztebl Int 2010; 107[42]: 733 741).
The pathogenesis of postoperative nausea remains unclear, but it has ...
New York University researchers have developed a method to shape solid materials using a corn starch solution. The process, devised by researchers in NYU's Courant Institute of Mathematical Sciences and Department of Physics, offers a potential technique for material cutting and manufacturing processes.
Their work is described in the journal Physical Review Letters.
Manufacturers use a variety of methods for shaping solid materials, ranging from laser cutting to high-speed jets of water. While altering the shape of such materials, such as glass, metal, or stone, is ...
BATON ROUGE – Genetic diseases impact millions around the world each and every day. Complex medical conditions with genetic predispositions, such as hypertension, can also weigh heavily on our lives. Susceptibility to hypertension has many genetic components and often goes undiagnosed until a person has signs of advanced disease.
Many imagine a day when science will give us the tools to discover how to work with these genetic issues and discover ways to not only diagnose, but to use them to our advantage as individuals. LSU Boyd Professor Mark Batzer and an international ...
NASA's infrared satellite imagery has confirmed that Tomas is intensifying as convection is strengthening and cloud tops within the system are getting colder.
Infrared imagery helps scientists detect cold top temperatures within a tropical cyclone, and Tomas' cloud tops have grown colder over the last 24 hours. Tomas showed strong convective activity in his center as indicated by high thunderstorms that were as cold as -63 degrees Fahrenheit. The colder the cloud tops, the higher and stronger the thunderstorms are that power the tropical cyclone. The infrared imagery ...
