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  • Albinism is a rare genetic condition where a person’s body isn’t able to make skin

  • color. But what exactly is albinism and how common is it?

  • Hey Guys, Julia here for DNews

  • Albinism is a genetic condition, where a person’s body isn’t able to make pigments, so people

  • with this condition have white skin and hair, with light blue or pink eyes.

  • Albinism is a complex disorder. You get your skin, eye and hair color from melanin, which

  • is distributed through a number of genes but if one of these genes carry a certain mutation

  • the amount of melanin that is distributed throughout your body changes. Or sometimes

  • this mutation will keep your body from producing any melanin at all.

  • Melanin is produced by cells called melanocytes which are mostly found in your skin and eyes

  • but also in your hair. People with darker skin have a higher concentration of melanin

  • in their skin as opposed to fair skinned people. Albinism is the absence of melanin completely.

  • And it’s not just people, any animal with pigment can be albino.

  • Albinism is passed down genetically. In most cases, there is someone in the family tree

  • who also has the condition. But not all cases are the same. There are actually many types

  • of albinism that all affect a different gene mutation.

  • Oculocutaneous albinism, which is when it affects your eyes, skin and hair, ranges from

  • type 1 to type 4 with varying degrees of melanin impact and affects 1 in every 20,000 people.

  • The most severe version of albinism is oculocutaneous albinism type 1 or OCA 1.

  • OCA 1 is caused by a mutation in 1 of 4 genes. It’s characterized by having pink or white

  • skin, eyes and hair. Some babies born with OCA type 1 do develop slight pigmentation

  • during their early childhood but many born with this type of albinism never do.

  • OCA type 2 is less severe than type 1, skin and eye color will be pale but hair color

  • is more likely to be red, yellow or auburn.

  • OCA type 3 mostly affects people who are darker skinned and will create a reddish light tan

  • tone along with auburn eyes. OCA type 4 is very related to type 2, it’s hard to diagnose

  • which type of albinism is at work and is best left to genetic testing.

  • Another type of albinism is ocular albinism type 1 (OA1), also called Nettleship-Falls

  • syndrome. Much like its name suggests only the eyes are affected by the genetic mutation,

  • while hair and skin will remain the same. This happens only when the genetic mutation

  • of an x chromosome is inherited so it occurs mostly in males. The eyes will appear blueish

  • pink, the iris is super translucent and the most important part of the eye - the fovea,

  • which is responsible for a sharp image - does not develop properly. However any degree of

  • albinism comes with vision problems which include being cross eyed, being sensitive

  • to light, rapid eye movement and functional blindness.

  • An estimated 1 in 20,000 people worldwide are born with it and affects about 20,000

  • people in the U.S. every year. OCA type 2 happens more frequently in African Americans,

  • Native Americans and in Sub-Saharan Africa. Nigeria has one of the highest prevalence

  • of Albinism in the world with over two million people affected.

  • There are many myths that surround albinism and why it happens. While it is true that

  • people with albinism can’t tan and many can get very serious sunburns, the chances

  • of getting skin cancer is just as high with anyone else who spends a lot of time in the

  • sun. Other myths include the belief that albinos posses magic traits or bring bad luck. Some

  • tribal communities in Africa persecute them, forcing them to leave their native communities

  • or be killed. Places like Tanzania are having an especially hard time controlling this myth,

  • where sacrifices and the belief that albino body parts bring good luck causes a spike

  • in albino hunting.

  • So do you have albinism? Know someone who has it? Tell us your story down in the comments

  • below.

Albinism is a rare genetic condition where a person’s body isn’t able to make skin

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為什麼有些人是白化病? (Why Are Some People Albino?)

  • 83 10
    Jeng-Lan Lee 發佈於 2021 年 01 月 14 日
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