3 blind mice, see how they… see again!
For the first time ever, blind animals have had their sight restored in a lab.
This revolutionary experiment was carried out in mice, by a group of scientists from the University of California. They used a process known as ‘gene therapy’. A gene – a unit of DNA which can carry the instructions to make a particular protein – was injected into the eye of the mouse.
The gene in question carried instructions for a special protein called a receptor, whose job is to detect light entering the eye, and send signals to the brain.
Injecting the gene into the blind eye provides the eye with the information to make new receptors, which therefore begins to sense light again.
When undergoing tests, the previously-blind mice behaved similarly to normal mice – indicating that they could see again.
This is a significant breakthrough as currently the only option for patients with blindness caused by damage to the retina is an implant connected to a video camera. This provides a resolution of about 100 pixels (compared with millions of pixels in normal vision) and is awkward and expensive.
“To the limits that we can test the mice, you can’t tell the [experimentally] treated mice’s behaviour from the normal mice without special equipment,” John Flannery, a UC Berkeley professor of molecular sight and biology, said in a press release. “It remains to be seen what that translates to in a patient.”
Smell test for Parkinson’s?
A Scottish woman has the uncanny ability to detect whether a person will develop Parkinson’s disease – by smelling them!
Joy Milne first noticed the smell on her husband, who was diagnosed with Parkinson’s at a later date. She linked the odour to the disease after detecting it on other people with the disease at a support group.
Parkinson’s is a brain disease linked to the death of cells in a particular part of the brain called the substantia nigra. Symptoms include the characteristic tremor and difficulty initiating and regulating movement in the body.
Joy has worked with the University of Manchester and is named in their paper, published in ACS Central Science, as a ‘Super Smeller’. In a test where she was given clothes worn by a set of people with Parkinson’s and clothes worn by people without the disease, she identified an impressive 11 out of 12 correctly.
Researchers aimed to investigate Joy’s ability using a machine called a mass spectrometer. This was used to analyse components of the sebum – an oily substance secreted from the skin – of people with Parkinson’s disease.
Analysis of the sebum samples of Parkinson’s patients revealed a distinct ‘signature’ of compounds including ‘altered levels of perillic aldehyde and eicosane’.
This information could enable earlier diagnosis of the disease, since the odour can be detected years before symptoms occur.
New research suggests humans may detect Earth’s magnetic field in a similar way to some birds and animals. ‘Magnetoreception’ as it is known, is common in a variety of animals, for example pigeons, who use it to help them navigate. An exact explanation for how animals do this has not yet been established.
It has never before been clear whether magnetoreception occurs in humans.
Research was carried out at Caltech and the University of Tokyo and published in the journal eNeuro. The findings indicate that the human brain responds unconsciously to changes in magnetic fields.
The researchers used a special metal cage to shield participants from external radio waves. They then sat participants in the dark, in silence, and monitored their brain waves with electrodes attached to the head. When the magnetic field was moved silently around the chamber, this appeared to be detected by people’s brains.
“Given the known presence of highly evolved geomagnetic navigation systems in species across the animal kingdom, it is perhaps not surprising that we might retain at least some functioning neural components, especially given the nomadic hunter-gatherer lifestyle of our not-too-distant ancestors. The full extent of this inheritance remains to be discovered,” says Joseph Kirschvink of Caltech.
by Molly Andrews