Albinism is an
inherited disorder that is characterised by little or no production of melanin
pigment. Type and amount of melanin produced determines colour of skin, hair
and eyes. There is no cure for albinism, however people suffering from this
disorder can take measures for protecting their skin and increase their vision.
also leads to social isolation and
is World Albinism Day?
mark the occasion of Albinism, United Nations has declared June 13 of every
year as, "International Albinism Awareness Day". This will be in effect from
2015 and would be observed on this day hereafter every year. The United Nations
aims to increase awareness and initiatives that can be taken to promote and
protect the human rights of persons with albinism. In addition, understanding
of albinism would help to close the gap between those untreated and treated.
As per estimates,
about one in every 17,000 people has some kind of albinism. In India alone
there are 70,000 people suffering from albinism. The condition can affect both
sexes equally, however one type known as ocular albinism (affecting eyes) is
more pronounced in males than females. Albinism can affect people from all
Albinism is an
inherited genetic condition. Many forms of albinism are recessive, which means
that child inherits one abnormal gene from each parent. Children who have
albinism are born to parents having normal pigmentation. These parents are the
1 in 75 people who are carriers of albinism. As the parents themselves do not
have albinism, but they are still able to pass abnormal gene to their child and
such type of inheritance is called autosomal recessive. If two people are
carriers of the albinism gene, odds increase by 1 in 4 that the child will
have albinism and 1 in 2 chance that the child will not have albinism but will
be a carrier and 1 in 4 chance that the child will neither be a carrier nor
have albinism. This can be simply explained by DNA (a molecule that carries
genetic information) in the albinism gene does not contain instructions for
body to create enough pigment that is much needed to carry out various
functions including vision.
1. Ocular Albinism (OA):
affects only eyes and not skin or hair. This results from X-linked chromosomal
inheritance and therefore occurs mainly in boys.
2. Oculocutaneous Albinism (OCA):
affects eyes, hair and skin. OCA includes different forms.
involves tyrosinase enzyme that converts amino acid tyrosine into melanin
(chemical responsible for colour of skin, eyes and hair). OCA1 is further classified into two groups
OCA1a and OCA1b.
people with this type of albinism have no pigment and no active
people with this type of albinism have some residual tyrosinase activity
and hence have some pigment. Decreased pigmentation is observed at birth,
but may increase slightly throughout their lived. People under this group
also have the ability to sun tan.
affects p-protein, another protein involved in melanin production. This
form is much more common in sub-Saharan Africans, African-Americans and
Native Americans. People in this group typically do not tan as they have
some pigment. Typical characteristics in people of this group are having
yellow, auburn, ginger or red hairs, eyes can be blue-gray or tan, skin is
white at birth.
mainly found in black South Africans, have reddish-brown skin, ginger or
reddish hair, hazel or brown eyes.
is clinically indistinguishable from OCA2 and involves SLC45A2 gene,
responsible for production of another protein involved in melanin
formation. This type is found in people of East Asian descent.
3. Hermansky-Pudlak Syndrome (HPS):
a rare type of albinism with an increased incidence in people of Puerto Rican
descent. Disorders found in people of this group are associated with bleeding,
bruising, lung problems and intestinal disorders.
4. Chediak-Higashi syndrome:
rare form of albinism associated with mutation in LYST gene. People in this
group have abnormality in certain types of white blood cells, thereby lowering
of resistance to infection. Signs and symptoms are same as in oculocutaneous
albinism, however hair is usually brown or blond with silvery sheen, skin is
creamy white to greyish.
5. Griscelli Syndrome:
a very rare type of albinism, only 60 known cases are available worldwide.
Similar to Chediak-Higashi Syndrome, there is deficiency in immune system and
is associated with neurological problems.
Mutation in one of
several genes is primary cause for albinism. These genes provide an instruction
that is useful in making one of several proteins involved in melanin
production. Melanin is produced by cells called as melanocytes, found in skin and
eyes. If mutation occurs then there is no melanin produced at all or
significant decline in amount of melanin. In some types of albinism, two copies
of mutated gene are inherited - one from each parent, for albinism to occur.
This is called recessive inheritance.
Lack of the pigment
melanin mainly affects colour of hair, skin and eyes.
albinism have very pale skin and will usually not tan or burn easily in the
sun. In some people, skin pigmentation
does not change at all and for some people, melanin production may begin or
rise during childhood and teen years, resulting in minor changes in
Exact colour of the
hair depends on melanin the body produces. For some people having albinism hair
is white or very light blonde. Some people have brown or ginger hair. In case
of Africans or Asians colour of the hair is yellow, reddish or brown. Hair
colour may also get darkened during early childhood.
Iris-the coloured part of the eye, lacks the
essential pigment required for colour of the eye. Due to which people having
albinism have very pale blue or grey eyes. The missing pigment can also lead to
other eye conditions such as:
Eyesight: either short sightedness (myopia) or long sightedness
(hyperopia), and low vision.
Distortion of a viewed image.
Eye is sensitive to light.
involuntary, irregular and rapid movement of the eye.
Eyes point in different directions.
As albinism is a genetic disorder, there
is little scope for treatment. Proper monitoring of eye and skin for any signs
of abnormalities is especially important.
For eyes, if myopia, hyperopia and astigmatism
, use of glasses or contact lenses
may correct the problem leading to improved vision. Regular eye test would also
be required to check prescription of eye glasses and contact lenses. Although
surgery is rarely required part for treatment of albinism, ophthalmologist may
recommend surgery on optical muscles to minimise Nystagmus. In case of
Strabismus, surgery may make the condition less visible, however won't improve
Lack of melanin in skin can prone to increased risk of sunburn and skin
cancer, caused by direct sunlight. People with albinism should wear sunscreen
having high sun protection factor (SPF) namely SPF 30. Also, going out should
be avoided when it is very hot. If out in the sun, sunglasses must be worn that
has UV filter and hat with loose-fitting clothing must be worn.