Help others to be mothers - please sign and share the Progress Educational Trust's petition, calling on the UK Government to #ExtendTheLimit on social egg freezing
Page URL: https://www.bionews.org.uk/page_93038

Do humans carry a gene for detecting the Earth's magnetism?

27 June 2011
Appeared in BioNews 613

Humans may retain a diminished ability to see the Earth's magnetic field, claims a new American study. Experiments were carried out to investigate the function of light-sensitive proteins called cryptochromes, in the eyes of fruit flies and Monarch butterflies. These proteins were found to endow these insects with the ability to detect magnetic fields. The same protein is also present in the human eye, raising the possibility that humans may also retain this ability to some extent.

'I would be very surprised if we don't have this sense; it's used in a variety of other animals. I think that the issue is to figure out how we use it', said Professor Steven Reppert at the University of Massachusetts Medical School, who led the study.

Many animals, such as migratory birds, visually detect the Earth's magnetic field in order to orientate themselves. The light-sensitive proteins, cryptochromes, are thought to be responsible for this geomagnetic navigation. In humans, the cryptochrome gene CRY2 is strongly expressed in a region of the eye called the retina. Cryptochromes are already known to regulate the human body clock, however their role in magnetoreception is less clear.

Fruit flies also express cryptochromes and are known to be able to detect magnetic fields. This can be detected by a change in direction in response to a magnetic field. In mutant fruit flies lacking cryptochromes, their magnetoreception ability was lost. Expressing the human CRY2 gene (hCRY2) in these mutant flies rescued their ability to perceive magnetic fields, suggesting that human cryptochromes are able to function in the same capacity as fruit fly cryptochromes.

'…We do not yet know whether this capability is translated into a downstream biological response in the human retina. Nonetheless, the transgenic findings with hCRY2, together with its anatomical location in the human retina and previous work showing field effects on the visual system, suggest that a reassessment of human magnetosensivitiy may be in order', state the authors of the study.

Human magnetoreception is not a new concept and was proposed over 20 years ago by Dr Robin Baker of the University of Manchester. Dr Baker conducted studies on human volunteers but was unable to determine the mechanism behind this theory.

'I think one of the things that put people off accepting the reality of human magnetoreception 20 years ago was the lack of an obvious receptor', said Professor Reppert. 'So these new results might actually be enough to tip the balance of credibility. I shall be fascinated to see'.

This study was published in the journal Nature Communications.

SOURCES & REFERENCES
Can humans actually sense the earth's magnetic field?
Time Techland |  22 June 2011
Human cryptochrome exhibits light-dependent magnetosensitivity
Nature Communications |  21 June 2011
Human eye protein senses Earth's magnetism
BBC News |  21 June 2011
Humans really DO have a sixth sense... that lets us detect magnetic fields (and we're not aware we have it)
Daily Mail |  23 June 2011
Magnetic Field Sensed by Gene, Study Shows
New York Times |  21 June 2011
The Eyes Have It: A Protein for Magnetic Sensing
Scientific American |  23 June 2011
RELATED ARTICLES FROM THE BIONEWS ARCHIVE
27 September 2010 - by Dr Rachael Panizzo 
Researchers have successfully transplanted retinal cone cells into blind mice, making progress towards a stem cell treatment for a form of blindness that causes degeneration of the eye's retina...
21 September 2009 - by Sarah Pritchard 
Scientists in the USA have used gene therapy to restore full vision to two male squirrel monkeys with red-green colour blindness, raising hopes that the technique might one day be used to treat humans. The researchers injected both monkeys with the human form of a gene which enables detection of the colour red. Five months after the treatment, the monkeys were able to successfully identify a red pattern on a background of grey dots....
6 March 2006 - by BioNews 
US researchers have identified mutations in two genes that together account for nearly three-quarters of all cases of age-related macular degeneration (AMD), a common cause of blindness in the elderly. The study, carried out by scientists based at Columbia University Medical Center in New York, builds on work published by...
14 August 2005 - by BioNews 
US scientists have used gene therapy to successfully treat mice with a rare genetic disorder that causes blindness, called retinoschisis. The researchers, based at the University of Florida Genetics Institute, say their method could eventually be used to treat a range of eye diseases in humans. Retinoschisis causes the retina...
30 July 2004 - by BioNews 
Short-sightedness, or myopia as it is technically known, affects around a quarter of the UK population and its incidence is on the increase around the world. In Singapore the percentage of the population with myopia rose from 25 per cent to 80 per cent in the last 30 years, with...
HAVE YOUR SAY
Log in to add a Comment.

By posting a comment you agree to abide by the BioNews terms and conditions


Syndicate this story - click here to enquire about using this story.