Albinism is a congenital disease. This disease
It implies the absence of the skin, hair, nails, and rainbow eye pigment melanin pigment shells. The name "albinism" comes from the Latin word «albus», which is translated into Russian as "white." This disease is known for a long time, because its description is even in the documents of ancient Rome and Greece.
Causes of albinism
Albinism occurs due to lack of the enzyme tyrosinase, or blockade. It is extremely important for melanin production (the name comes from the Greek word «melanos», which in Russian means "black"). Skin color is determined by the amount of melanin in it. What it is, the darker the skin. In those cases where problems with the development of tyrosinase is observed, cause of albinism is considered a mutation in genes.
Albinism is inherited from the parents. He appears in a child if both parents are carriers of the defective gene. When the defective gene is present in only one parent, albinism does not develop in children, but the body is still a mutated gene that can be passed to the next generation. This whole process is called autosomal recessive inheritance.
Types of albinism
Albinism is divided into three types:
Albinism in humans with total views observed from birth autosomal recessive. In addition to depigmentation of the skin appears dry, hyper-or hypotrichosis (often in open areas), in violation of the sweat glands. Patients can easily develop keratomas, telangiectasia, epithelioma, actinic cheilitis and sunburn. Observed infertility, cataracts, strabismus, poor eyesight (due to refractive disorders), microphthalmia, mental retardation, abnormal development, immune deficiency (for this reason, are often subject to infectious diseases) and a decrease in life expectancy. People suffer from photophobia and horizontal nystagmus. Since the pupil no pigment, they have a red hue.
Partial albinism, which is also called piebaldizmom also evident from birth. Sometimes it can be a symptom syndromes Klein-Waardenburg, Chedaka-Higashi, Mende, cross-MakKyuzika Brin, Tietze, Hermanski-Pudlaka. Typical manifestations are areas achromia having clear boundaries, but an irregular shape, the surface of which there are small specks of dark brown color. In general, partial albinism in humans occurs on the face, legs and abdomen, as well as the hair strands Aged color. At close to the skin of these spots are often observed increased pigmentation. This type of albinism is inherited in an autosomal dominant manner.
Incomplete albinism, which is also called albinoidizmom appears only hypopigmentation of hair, iris eyes and skin. Very rarely observed photophobia. The reason is the low activity of tyrosinase, but its synthesis is not blocked. Partial albinism is inherited in an autosomal dominant manner, at least - recessive.
Also distinguish eye and skin-ocular albinism (ksantizm). The cause is ksantizma mutation in one of the 4 genes. The signs of albinism are the variety of skin, hair pigmentation, pigmentation of the iris of eyes and vision problems. Divided into four types:
- Type 1 occurs due to mutations in the eleventh chromosome. This type of albinism occurs in humans from birth. Skin and hair color of milk sick, and his eyes - blue. Sometimes age can begin to make melanin: the eyes and the skin becomes slightly darker.
- Type 2 occurs due to mutations in the fifteenth chromosome. The skin is white or light brown hair - yellow, reddish or golden brown eyes have a yellowish-brown or blue-gray color. Basically ill residents of the Sahara desert, blacks and Indians living in North America. Under the sun on the skin almost instantly appear freckles.
- 3 Type provoke mutations in the ninth chromosome. It is very rare. The skin is brown with a reddish tinge, his eyes - red hair has a red tint. Basically ill people living in southern Africa.
- 4 type and is extremely rare and is caused by a mutation in the fifth chromosome. Sick, mostly people living in the south-east Asia. The symptoms are the same as the second type.
The symptoms of albinism
People with albinism, skin is very soft pale pink color, so it is easy to shine through the capillaries. The skin is very prone to the appearance of telangiectasia (spider veins), epitaleom, keratitis and sunburn. It is also a sign of albinism are very thin and soft hair, which are white, more rarely - yellow.
Today is not yet developed such treatment of albinism in humans, which would be effective. Strabismus can be corrected only by adjusting the eye muscles and vision, as well as partial or total types of albinism, you can give the skin a yellowish hue, using 90 to 180 mg of beta-carotene per day.
Advice for patients
Even if the window is not so much the sun shines, you still need to be sure to wear sunglasses and protect the skin by special means having a sun protection factor (SPF) of at least 30. In hot weather, it is not recommended to go out. Clothing should be made of natural materials and cover the entire surface of the body. It is also advisable to wear hats with wide enough field. A must is a visit to a neurologist in a strict order, ophthalmologist and dermatologist.
Complications of albinism
Albinism in humans provokes complications as the physical side, and by the emotions, even to complete social isolation. Physical - skin cancer and severe sunburn. Emotional - discrimination on the part of others, depression and stress.
Prevention of albinism
There is only one way to avoid the disease - genetic testing of couples who are about to become parents. Thanks to modern technology, you can easily detect defects on the part of genetics, the couple, who later become a cause of albinism in children.