Do you inherit bad eyesight?

Did you inherit vision problems from your parents?

We all know that our genes are responsible for lots of our characteristics, from hair and eye colour, to personality, and even for skills like singing and sporting ability. But have you ever considered how much of your eyesight and predisposition to eye diseases is inherited? We’re going to have a look into a few of the different common issues with eyesight and eye health, and at your probability of developing these with regards to your parents’ own eye health. Scientists have identified over 500 different genes which relate to eye disorders, and we’re focusing on just a handful of the most common issues here.

While most common vision problems  can be attributed to genetics, it’s important to note that poor eyesight or development of eye conditions or diseases aren’t solely based on inherited factors. It’s also down to factors caused by your own health, environment, lifestyle, or even ageing. We’ll cover what you can do in these areas to help preserve good eye health and to protect your vision.

Is short-sightedness inherited from your parents?

Short-sightedness (also known as myopia) occurs when your eye is too short to properly process the images you’re looking at. This results in anything further away than your near vision being blurry, and requires glasses, contact lenses, or laser eye surgery in order to be rectified.  Common signs of myopia include eye strain, headaches and blurry distance vision.

If two short-sighted parents have a child together, there is a 1 in 3 chance that their child will also be short-sighted. If a child only has one parent who is short-sighted, there is a 1 in 5 chance they will be short-sighted. If neither parent is short-sighted, the chances of them having a child who is short-sighted are 1 in 40.

Is long-sightedness genetic or not?

Long-sightedness (also known as hyperopia) occurs when your eye is too long to be able to focus on images close to you. In this case, you will struggle to focus on objects like a book or your phone, but your vision further away is fine. Again, this can be corrected by wearing glasses or contact lenses, or by having laser eye surgery.

You are more likely to develop long-sightedness if one or both of your parents are also long-sighted. This is because refractive disorders are caused by inherited genetic markers. However, research on inherited long-sightedness is limited and knowledge around this develops constantly while studies are on-going.

You can also develop age-related long-sightedness in your 40s, which is known as presbyopia. This occurs when the lens in your eye stiffens with age and can no longer flex as easily to focus on objects or text close to you. While this isn’t inherited as such – as it happens to everybody once they reach middle age – it’s possible that the severity and age of onset of your presbyopia is influenced by your parents’ experiences with presbyopia.

Are cataracts caused by bad genes?

Cataracts occur as a normal part of the ageing process, forming when proteins in the eye begin to clump together. This results in blurry, clouded vision, dimmed colours and a yellowish tinge across your visual field. You may also feel particularly sensitive to light. Around 400,000 cataract procedures are carried out in the UK each year, so it’s clear that a lot of people suffer with poor vision caused by cataracts.

While cataracts do occur naturally, they tend to run in some families more than others. Not everyone will develop cataracts but, if close members of your family like your parents or grandparents had them, your risk is also higher. If left untreated, cataracts can cause severely impaired vision and even blindness. Thankfully, cataracts are easily treatable with a simple procedure which is usually completed within 20 minutes. There are a number of risk factors that increase your chance of developing cataracts, such as smoking, drinking alcohol, and spending a lot of time in the sun so, if you have a family history of cataracts, you should be especially vigilant about these risk factors.

Is glaucoma hereditary?

Glaucoma occurs when you have abnormally high eye pressure, leading to damage of the optic nerve. It can occur for a number of reasons, often due to the eye’s drainage angle being blocked, but it can also occur due to high blood pressure, in turn causing high eye pressure, leading to peripheral vision damage occurring. Glaucoma is far more likely to have been inherited than to occur randomly – in fact, if you have a family history of glaucoma, you are up to 9 times more likely to develop it yourself. Knowing your family history when it comes to glaucoma allows you to have regular check-ups with your optician. This is especially important as severe damage caused by glaucoma occurs before you have visual symptoms, and can only be picked up at an eye test.

You can lower your chances of developing glaucoma by:

• Watching your weight
• Reducing your caffeine consumption to maintain a low eye pressure
• Exercising daily

Can macular degeneration be inherited?

Age-related macular degeneration (AMD) runs in some families more than others and is more likely to develop due to a family predisposition than it is to occur randomly. AMD is a disease which affects a part of your eye called the macula, which is the central part of your retina. The macula is responsible for your central vision, colour vision, and fine detailed vision, so these are the elements of your sight which are impacted by AMD. AMD mainly attacks your central vision which makes tasks like reading, recognising faces and even using your phone very difficult.

You are 3-4 times more likely to develop AMD if one of your parents or siblings has AMD. If you know you’re related to somebody who has dealt with AMD previously, you should ensure you go for regular eye tests. Like with plenty of other eye conditions, by the time you can see damage in your visual field, it is too late to restore lost vision. Attending regular checks with your optician allows any problems to be picked up quickly and for you to have any necessary treatment as soon as possible.

Risk factors for AMD include obesity and high blood pressure (both of which are also genetic), as well as a history of heart disease and high cholesterol. Working to control these risk factors by changing your diet and exercise habits will reduce your AMD risk – as well as giving up smoking and reducing your alcohol intake. Read more about AMD on our blog.

Is colour blindness hereditary?

Colour blindness does not change or worsen over time, but it is inherited from your parents. It is a condition which prevents someone from distinguishing between particular colours – most commonly reds and greens. It affects two types of cells in your retina; rods and cones. There are around 100 million rods in your retina, and between 6 and 7 million cones. Rods detect light and dark but cannot distinguish between different colours, while your cone cells are responsible for colour vision and perceive either red, green or blue shades. Your colour vision relies on all three types of cones working effectively, and colour blindness occurs when one cone colour isn’t functioning properly. A person with fully functioning colour vision has a small degree of overlap of their cones, but a person with colour blindness has cones which overlap too much, limiting their perception of colour. 

Colour blindness is passed down through the X chromosome and is inherited from your parents. Females have two X chromosomes, while males have one X and one Y chromosome. A child always receives an X chromosome from the mother, while the father can give either an X or Y chromosome – so the chromosome a baby receives from its father determines its gender. More men are colour blind than women because of a process which All About Vision have neatly summarised:

• A daughter who inherits the colour-deficient gene from her father will be a carrier of the gene but she will not be colour blind (unless her mother carries the gene, and she receives a paired colour-deficient gene from her mother as well)
• If a daughter inherits the X-linked trait from both her father and her mother, then she will be colour blind.
• When a mother passes along this X-linked trait to her son, he will inherit the colour vision deficiency and have trouble distinguishing reds and greens

Looking after your vision

You should have regular eye tests anyway (at least once every 2 years), but if you have a family history of any of the sight-threatening eye conditions we’ve just discussed, you should be especially vigilant about attending. In some cases, yearly eye tests are recommended so that any changes to your vision and eye health can be monitored. Factors which can contribute to poor eyesight include:

• Exposure to chemicals
• Bacteria in the eye
• Toxic gases and pollutants
• Drug use
• Overexposure to UV rays
• Some cosmetics or makeup
• High blood pressure

Be sure to avoid these where possible, including any known allergens you have, in order to promote good eye health and reduce your risk of vision problems. If you’d like to keep up to date with tips on eye health, make sure to check our blog regularly for guidance. If you have any questions about ways you can improve your vision with laser eye surgery or lens treatments, please give us a call on 0800 093 1110 or email enquiry@optimax.co.uk to learn more.