24 new genes behind short-sightedness identified
London: Scientists have discovered 24 new genes that cause refractive errors and myopia (short-sightedness).Myopia is a major cause of blindness and visual impairment worldwide, and currently there is no cure.
These findings could lead to finding better treatments or ways of preventing the condition in the future.
During visual development in childhood and adolescence the eye grows in length, but in myopes it grows too long, and light entering the eye is then focused in front of the retina rather than on it. This results in a blurred image. This refractive error can be corrected with glasses, contact lenses or surgery.
However, the eye remains longer, the retina is thinner, and this may lead to retinal detachment, glaucoma or macular degeneration, especially with higher degrees of myopia. Myopia is highly heritable, although up to now, little was known about the genetic background.
They analysed genetic and refractive error data of over 45,000 people from 32 different studies, and found 24 new genes for this trait, and confirmed two previously reported genes. Interestingly, the genes did not show significant differences between the European and Asian groups, despite the higher prevelance among Asian people.
The new genes include those, which function in brain and eye tissue signalling, the structure of the eye, and eye development. The genes lead to a high risk of myopia and carriers of the high-risk genes had a tenfold increased risk.
It was already known that environmental factors, such as reading, lack of outdoor exposure, and a higher level of education could increase the risk of myopia. The condition is more common in people living in urban areas.
An unfavourable combination of genetic predisposition and environmental factors appears to be particularly risky for development of myopia. How these environmental factors affect the newly identified genes and cause myopia remains intriguing, and will be further investigated by the consortium.
Professor Chris Hammond from the Department of Twin Research and Genetic Epidemiology at King`s College London, and lead author of the paper, said: "We already knew that myopia - or short-sightedness - tends to run in families, but until now we knew little about the genetic causes. This study reveals for the first time a group of new genes that are associated with myopia and that carriers of some of these genes have a 10-fold increased risk of developing the condition."
These findings have been published in the journal Nature Genetics.
`Evil patch` inside brains of killers & rapists discovered 
London:
A German neurologist claims to have found the area of the brain where
evil lurks in killers, rapists and robbers, saying that the "evil patch"
lies in the central lobe and shows up as a dark mass on X-rays.Bremen scientist Dr Gerhard Roth discovered it when investigating violent convicted offenders over the years for German government studies, the Daily Mail reported.
"We showed these people short films and measured their brain waves. Whenever there were brutal and squalid scenes the subjects showed no emotions. In the areas of the brain where we create compassion and sorrow, nothing happened," he said.
The dark mass at the front of the brain, he said, appears in all scans of people with records for criminal violence.
"When you look at the brain scans of hardened criminals, there are almost always severe shortcomings in the lower forehead part of the brain," he added.
He said that there are cases where someone becomes criminal as a result of a tumour or an injury in that area, and after an operation to remove the tumour , that person was completely normal again.
This is definitely the region of the brain where evil is formed and where it lurks, he said.
ANI
First Published: Wednesday, February 06, 2013, 14:38
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