Genetics of Albinism
For nearly all types of albinism both parents must carry an albinism gene to have a child with albinism. Because the body has two sets of genes,a person may have normal pigmentation but carry the albinism gene. If a person has one gene for normal pigmentation and one gene for albinism, he or she will have enough genetic information to make normal pigment. The albinism gene is "recessive" — it does not result in albinism unless a person has two copies of the gene for albinism and no copy of the gene that makes normal pigment.

When both parents carry the gene, and neither parent has albinism, there is a one in four chance at each pregnancy that the baby will be born with albinism. This type of inheritance is called autosomal recessive inheritance.

(The most common type of ocular albinism follows a different pattern of inheritance. The NOAH Information Bulletin "Ocular Albinism" has more information.)

Each parent of a child with oculocutaneous albinism must carry the gene. Both the father and the mother must carry the gene for albinism. For couples who have not had a child with albinism, there is no simple test to determine whether a person carries a gene for albinism. Researchers have analyzed DNA of people with albinism and found the changes that cause albinism, but these changes are not always in exactly the same place, even for a given type of albinism. Therefore the tests for the gene may be inconclusive.

If parents have had a child with albinism previously, there is a way to test in subsequent pregnancies to see if the fetus has albinism. The test uses amniocentesis (placing a needle into the uterus to draw off fluid). Cells in the fluid are examined to see if they have an albinism gene from each parent.

For specific information and genetics and testing, seek the advice of a qualified genetic counselor. Genetic counselors are usually associated with universities and children's hospitals. The National Society of Genetic Counselors at (610) 872-7608 in Philadelphia maintains a referral list.

Those considering prenatal testing should be made aware that people with albinism can adapt well to their disabilities, and lead fulfilling lives.

Vision Rehabilitation: Eye conditions common in albinism include

Nystagmus, irregular rapid movement of the eyes back and forth.
Strabismus, muscle imbalance of the eyes ("crossed eyes" or "lazy eye")
Sensitivity to bright light and glare.
People with albinism may be either far-sighted or near-sighted, and often have astigmatism (distortion of a viewed image).
These eye problems result from abnormal development of the eye because of lack of pigment. The retina, the surface inside the eye that receives light, does not develop normally before birth and in infancy. The nerve signals from the retina to the brain do not follow the usual nerve routes. The iris, the colored area in the center of the eye, does not have enough pigment to screen out stray light coming into the eye. (Light normally enters the eye only through the pupil, the dark opening in the center of the iris, but in albinism light can pass through the iris as well.)

For the most part, treatment of the eye conditions consists of visual rehabilitation. Surgery to correct strabismus may improve the appearance of the eyes. However, since surgery will not correct the misrouting of nerves from the eyes to the brain, surgery will not provide fine binocular vision. In the case of esotropia or "crossed eyes," surgery may help vision by expanding the visual field (the area that the eyes can see while looking at one point).

People with albinism are sensitive to glare, but they do not prefer to be in the dark, and need light to see just like anyone else. Sunglasses or tinted contact lenses help outdoors. Indoors, it is important to place lights for reading or close work over a shoulder rather than in front.

Various optical aids are helpful to people with albinism, and the choice of an optical aid depends on how a person uses his or her eyes in jobs, hobbies, or other usual activities. Some people do well using bifocals which have a strong reading lens, prescription reading glasses, or contact lenses. Others use hand-held magnifiers or special small telescopes. Some use bioptics, glasses which have small telescopes mounted on, in, or behind their regular lenses, so that one can look through either the regular lens or the telescope. Newer designs of bioptics use smaller light-weight lenses. Some states allow the use of bioptic telescopes for driving. (See also NOAH bulletin "Low Vision Aids.)

Optometrists or ophthalmologists who are experienced in working with low vision patients can recommend various optical aids. Clinics should provide aids on trial loan, and provide instruction in their use. The American Foundation for the Blind (1-800-AFB-LIND) maintains a directory of low vision clinics.