Albino people: genetics and problems they suffer

The DNA that each cell in your body contains contains all the information necessary for the development and functioning of an organism. Therefore, any defect that is located in the genetic material can degenerate into a malfunction and health problems.

A clear example is albinism: This genetic condition is characterized by the total or partial absence of pigmentation (melanin) in the skin, hair and iris of the eye.

The albino condition is not exclusive to humans, it also occurs in animals (a memorable example was Copito de Nieve, the albino gorilla at Barcelona Zoo) and in plants. In the latter case, they have an absence of other classes of pigments, such as carotenes, since they do not naturally present melanin.

However, the lack of pigmentation is not the only characteristic of this alteration. Albino people, in fact, have many associated problems, both biological and social.

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The role of pigments

Pigmentation in humans is in charge of cells known as melanocytes

, which make the two kinds of melanin inside from the amino acid tyrosine: eumelanin (dark) and pheomelanin (light).

The combination in different proportions of these two originates the range of colors of eyes, hair and skin. Its main function is the protection of other cells against ultraviolet light, which is harmful to DNA.

Genetic causes of albinism

Albinism has an important genetic component that presents an autosomal recessive inheritance. It is simple to understand: our genetic material is made up of 23 pairs of chromosomes, one half comes from the mother and the other from the father (each pair has two homologous genes in the same position, one per pair, which is known as allele). Normally, only one of the two genes on an allele is needed to work well for proper function. Well, in this case we speak of autosomal recessive because the two genes of that allele are wrong.

For this reason, it is explained how non-albino parents can have a child with this condition, since parents are carriers, each has a wrong gene.

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There are different types of albinism

Not all albino people have the same genetics, but there are different classes that depend on the gene that is affected. The truth is that not all of them lead to the loss of skin and hair pigmentation, they only share the decrease in visual acuity for various alterations in the eye.

Classically, they have been defined two large groups: oculocutaneous (OCA) and ocular (OA) albinism. As its name suggests, the first affects melanin both in the eye and in the skin and hair, unlike the second, in which only the melanin present in the iris is affected. Lack of pigmentation can also be associated with other serious organic disorders, such as Hermansky-Pudlak syndrome.

At the moment up to 18 genes are known to be involved, with 800 possible mutations. For example, one of the most common types in the West is OCA1, in addition to being the most severe, in which the affected gene is the one that synthesizes the enzyme tyrosinase (TYR). This protein is responsible for transforming the amino acid tyrosine into melanin within melanocytes. Of course, if the enzyme does not work, melanin is not synthesized in the body.

Problems that it entails

People with albinism who have a total or partial lack of melanin in their skin and hair have trouble tolerating solar radiation. They are easy to redden and the probability of suffering increases skin cancer, so they need to protect themselves from the sun, either by clothing or suitable cream.

The lack of pigmentation in the eye, a common characteristic of all its types, produces photophobia, that is, direct light is not well supported. It is common to wear sunglasses to protect your eyes from light. It must be added that albino people also have different visual anomalies that hinder their acuity, so one of their great problems is in vision.

Albinos in the world

The worldwide frequency of albinism is low, 1 in 17,000 people. But there are different types, each with its prevalence, and their degree of dispersion also depends on the point of the world that is being discussed. For example, in Japan there is a high prevalence of the OCA4 type, due to there being some inbreeding; and on the island of Puerto Rico, which is considered the country with the highest incidence of this condition genetics there are many more people affected in its most dangerous aspect, that of the syndrome Hermansky-Pudlak.

Africa is another example. The continent where albinos appear most frequently, in addition, does not make things easy for people albinos: due to archaic beliefs, some cultures kill these people and tear them to pieces with the aim of from sell them to shamans for their spells. In the case of women it is even worse, since it is thought that they have the ability to eradicate HIV through sexual intercourse, so they rape them and are infected with the disease. Added to the fact that Africa is the region of the world with the highest solar radiation, the quality of life of albino people is appalling.