Tag Archive eyes

Amazing Eyes

Brown eyes 6.10.14We don’t often give our eyes as much thought as we should, that is until something goes wrong and our vision is affected. But when you learn more about eyes, you realize just how amazing they are. Here are a few facts you may enjoy:

1. Eyes began to develop 550 million years ago. The simplest eyes were patches of photoreceptor protein in single-celled animals.

2. Your eyes start to develop two weeks after you are conceived.

3. The entire length of all the eyelashes shed by a human in their life is over 98 feet with each eye lash having a life span of about 5 months.

4. To protect our eyes they are positioned in a hollowed eye socket, while eyebrows prevent sweat dripping into your eyes and eyelashes keep dirt out of your eyes.

5. Your eyeballs stay the same size from birth to death, while your nose and ears continue to grow.

6. An eye is composed of more than 2 million working parts.

7. Only 1/6 of the human eyeball is exposed.

8. Corneas are the only tissues that don’t have blood.

9. The human eye weights approximately just under an ounce and is about an inch across.

10. An eye cannot be transplanted. More than 1 million nerve fibers connect each eye to the brain and currently we’re not able to reconstruct those connections.

11. 80% of our memories are determined by what we see.

12. Eyes heal quickly. With proper care, it takes only about 48 hours to repair a minor corneal scratch.

13. There are about 39 million people that are blind around the world.

14. 80% of vision problems worldwide are avoidable or even curable.

15. Humans and dogs are the only species known to seek visual cues from another individual’s eyes, and dogs only do this when interacting with humans.

16. A fingerprint has 40 unique characteristics, but an iris has 256, a reason retina scans are increasingly being used for security purposes.

17. People who are blind can see their dreams if they weren’t born blind.

18. “Red eye” occurs in photos because light from the flash bounces off the back of the eye. The choroid is located behind the retina and is rich in blood vessels, which make it appear red on film.

19. 80% of what we learn is through our eyes.

20. Eyes are the second most complex organ after the brain.


Susan DeRemerSusan DeRemer, CFRE
Vice President of Development
Discovery Eye Foundation

Tags, , , , , , ,

blueeyesfeature

Scientists found something huge..

…..that all blue-eyed people have in common

Scientists working to uncover our DNA history.

You’ve probably wondered, why do we have the colour eyes we do? It comes down to our genes. And scientists are really starting to get to the bottom of it.

Produced By Matt Johnston. Research by Lauren Friedman. 

RABGGTA is a candidate gene for hair color.

Originally posted by businessinsider.com

New research shows that people with blue eyes have a single, common ancestor. A team at the University of Copenhagen have tracked down a genetic mutation which took place 6-10,000 years ago and is the cause of the eye colour of all blueeyed humans alive on the planet today.

Studies carried out by scientists from the Institute of Forensic Genetics at the University of Copenhagen have concluded that all blue-eyed people share a common ancestor, someone who lived 6,000 to 10,000 years ago near the area by the Black sea.

Researchers analyzed and compared the unique genetic make-up of the chromosomes in the iris from 155 blue-eyed individuals from diverse regions such as Denmark, Turkey and Jordan.

All of the subjects that participated in the study had the exact same genetic “mutations” in specific chromosomes of the eye with very little variation on the genes, indicating that the “mutation” responsible for blue-eyes first arose and spread relatively recently.

________________________________________

Abstract

The human eye color is a quantitative trait displaying multifactorial inheritance. Several studies have shown that the OCA2 locus is the major contributor to the human eye color variation. By linkage analysis of a large Danish family, we finemapped the blue eye color locus to a 166 Kbp region within the HERC2 gene. By association analyses, we identified two SNPs within this region that were perfectly associated with the blue and brown eye colors: rs12913832 and rs1129038. Of these, rs12913832 is located 21.152 bp upstream from the OCA2 promoter in a highly conserved sequence in intron 86 of HERC2. The brown eye color allele of rs12913832 is highly conserved throughout a number of species. As shown by a Luciferase assays in cell cultures, the element significantly reduces the activity of the OCA2 promoter and electrophoretic mobility shift assays demonstrate that the two alleles bind different subsets of nuclear extracts. One single haplotype, represented by six polymorphic SNPs covering half of the 3? end of the HERC2 gene, was found in 155 blue-eyed individuals from Denmark, and in 5 and 2 blue-eyed individuals from Turkey and Jordan, respectively. Hence, our data suggest a common founder mutation in an OCA2 inhibiting regulatory element as the cause of blue eye color in humans. In addition, an LOD score of Z = 4.21 between hair color and D14S72 was obtained in the large family, indicating that

link.springer.com

_______________________________________

Sharing the info.

iamwill

Tags, , , ,

Aging Eyes Make an Economic Impact

Aging Eyes Make an Economic Impact

Originally posted by huffingtonpost.com
by Maureen Cavanagh: President Vision Impact Institute

Is it hard for you to read this blog on your smartphone? Do you have trouble reading a magazine, menu or the information on a prescription bottle? Does holding text away from your body at arm’s length actually help you focus?

If you answered “yes” to those questions, you might have presbyopia, the progressively diminishing ability of the eye to focus on up-close items, which for many becomes noticeable around the age of 40. The word originated with the Greek word “presbus” for old man combined with “?ps” for eye. Yes, I quite prefer the term presbyopia to “old man eyes.”

Don’t worry: You’re not alone. Presbyopia is actually a widespread problem — and it affects almost everyone at some point in their lives. In 2011, there were 1.272 billion cases of presbyopia reported around the globe. Of those, one-third were among working-age people 40-49 and another 41 percent were ages 50-64.

Vision impairment, such as presbyopia, can compromise a person’s quality of life because it reduces the capacity for everyday activities: reading, working, driving, etc. A major concern with presbyopia is that the people most affected by it — people over 40 — are likely to be in their prime working years. That can and does have a negative impact on global productivity.

A study by Kevin D. Frick, Ph.D., and others, highlighted on the Vision Impact Institute website, estimates a global productivity loss of more than $11 billion due to presbyopia for the 244 million cases worldwide among people younger than 50. Take into account all the cases of those under 65 and assumed to be productive, and the productivity loss increases to more than $25 billion.

The good news is that almost all presbyopia cases can be easily fixed with corrective lenses. The study points out that if those cases achieved the presbyopia correction level that Europe enjoys today — 96 percent — the global productivity loss deflates to $1.390 billion, a manageable 0.002 percent of the world’s economy.

The bottom line is that presbyopia has a significant negative burden on global productivity, and correction would provide an opposite positive boost, especially in lower-income countries. For example, Africa has only a 6 percent correction rate for presbyopia. Increasing that could tangibly boost the economies of African nations and the well-being of their citizens.

A fundamental way to improve vision health around the world, especially in developing countries, is access to eye care. Research has shown that recommended eye care that targets eye diseases and refractive errors, such as presbyopia, can immediately and cost effectively remedy half of reported vision problems.

The U.S. is not exempt from this issue, as the problem persists here in our affluent country as well. Blurry vision is a bigger problem than just not seeing the TV. Older Americans with moderate or extreme vision loss are more likely to suffer from diabetes, heart disease or stroke than those without vision loss, according to a reporton aging vision from the National Center for Chronic Disease Prevention and Health Promotion posted on the Vision Impact Institute website. The report, which gathered data from 19 states, also found that those with vision loss are more likely to report fair or poor health — instead of very good or excellent health — than their neighbors with better sight.

So the best step any of us can take to ensure good eye health is to make sure we have a comprehensive eye exam at least once a year. And if your eye doctor prescribes glasses (or contact lenses), don’t delay getting them. Through simple and regular steps such as an annual eye exam we can be more productive and improve our quality of life.

Originally posted by huffingtonpost.com
by Maureen Cavanagh

Tags, ,