We may assume that increased stature and breadth imply some sort of inherent physical superiority, and if such an assumption is valid we have in man evidence that albinism is correlated not with constitutional defectiveness but with greater perfectness.
Church, A Chemical Study of Vegetable Albinism, Journ.
In the condition known as albinism there is a congenital deficiency or entire absence of pigment.
Allen, "Mendel's Law and the Heredity of Albinism," Proc. Amer.
Albinism occurs in all races of mankind, among mountainous as well as lowland dwellers.
Albinism appears, in the processes of heredity, to be sometimes indissolubly correlated with certain peculiar traits.
Before we can inquire into the cause and meaning of albinism it will be necessary first to consider the nature of pigmentation.
An albino is a homozygote; that is, all its gametes are carrying the character of albinism and none of them bear the alternative character - the allelomorph - of pigmentation.
Now such a gametic (egg or sperm) constitution can only result when two individuals, all or some of whose gametes are pure with regard to the character albinism, meet in fertilization.
A b X N N(A) N+2N(A)+A No other rational explanation of the close relationship between albinism and cousin marriages is at present forthcoming.
Partial albinism in this case was undoubtedly correlated with some inherent constitutional defect, in virtue of which the individuals characterized by it were injuriously affected by the juices of a plant quite innocuous to their pigmented brethren.
Such cases suggest that we should be more correct in regarding, not albinism as correlated with constitutional defects, but rather pigmentation as correlated with powers of immunity or increased resistance against certain injurious processes.
We are not aware of any but two of these albinos having ever turned into the perfect Amblystoma form, as happened in Paris in 1870, the albinism being retained.
The chief or only changes which domestication seems to have induced in its appearance are a tendency to albinism generally shown in the plumage of its lower parts, and frequently, though not always, the conversion of the colour of its legs and 1 Columella (De re rustica, viii.
Following our move to Devon we saw an ophthalmologist at Torbay hospital who said he thought Matthew had ocular albinism.
Living with ocular albinism Our son, Sebastian, was born in November 1992.
The ocular findings in albinism include nystagmus, decreased visual acuity; hypopigmentation of retinal tissue, and macular hypoplasia.
ocular albinism Our son, Sebastian, was born in November 1992.
Albinism, with which variegated foliage may be considered, concerns a different set of causes, still obscure, and usually regarded as internal, though experiments go to show that some variegations are infectious.
In heredity, complete albinism among animals is always recessive; and partial albinism (piebald) is always recessive to complete pigmentation (self-coloured).
The recessive nature of albinism and its distribution in Mendelian fashion is almost certainly as true for man as for lower forms. This has been shown by W.
Certain individuals with chronic medical conditions such as Albinism or those who are on certain chronic medications to treat their medical condition may also be at higher risk.
Albinism is an inherited condition that is present at birth.
Many types of albinism exist, all of which involve lack of pigment in varying degrees.
The most common type of albinism is oculocutaneous albinism, which affects the eyes, hair, and skin.
Everyone with oculocutaneous albinism experiences abnormal flickering eye movements (nystagmus) and sensitivity to bright light.
The second most common type of the condition is known as ocular albinism, in which only the eyes lack color; skin and hair are normal.
Some types of ocular albinism cause more problems, especially eye problems, than others.
Albinism is also referred to as hypopigmentation.
Albinism is a rare disorder found in fewer than five people per 100,000 in the United States and Europe.
Although albinism can affect all races, other parts of the world have a much higher rate; for example, albinism is found in about 20 out of every 100,000 people in southern Nigeria.
The parents of most children with albinism have normal hair and eye color for their ethnic background and do not have a family history of albinism.
Many people with albinism do not have melanin pigment in their skin, do not tan with exposure to the sun, and as a result develop sunburn.
Over time, people with albinism may develop skin cancers if they do not adequately protect their skin from sun exposure.
Albinism is a autosomal recessive disease, which means that a person must have two copies of the defective gene to exhibit symptoms of the disease.
Because the task of making melanin is complex, there are many different types of albinism, involving a number of different genes.
It is also possible to inherit one normal gene and one albinism gene.
About one in 70 people are albinism carriers, with one defective gene but no symptoms; they have a 50 percent chance of passing the albinism gene to their child.
However, if both parents are carriers with one defective gene each, they have a one in four chance of passing on both copies of the defective gene to the child, who will have albinism.
There is also a type of ocular albinism that is carried on the X chromosome and occurs almost exclusively in males because they have only one X chromosome and, therefore, no other gene for the trait to override the defective one.
One of the myths about albinism is that it causes people to have pink or red eyes.
In fact, people with albinism can have irises varying from light gray or blue to brown.
If people with albinism seem to have reddish eyes, it is because light is being reflected from the back of the eye (retina) in much the same way as happens when people are photographed with an electronic flash.
In addition, albinism does not cause blindness.
The doctor should be called when a person with albinism exhibits symptoms such as photophobia that cause discomfort.
The parent of a child with albinism should also call the doctor if the child bruises easily or has unusual bleeding, such as repeated nosebleeds or bloody diarrhea.
It is not always easy to diagnose the exact type of albinism a person has.
In the early 2000s, a blood test has been developed that can identify carriers of the gene for some types of albinism; a similar test during amniocentesis can diagnose some types of albinism in an unborn child.
A chorionic villus sampling test during the fifth week of pregnancy may also reveal some types of albinism.
This test is the source of the names of two types of albinism: "typos" and "ty-neg."
In some types of albinism, a genetic defect in tyrosinase means that the amino acid tyrosine cannot be converted by tyrosinase into melanin.
There is no treatment that can replace the lack of melanin that causes the symptoms of albinism.
For reading, children with albinism may or may not need materials with large print text, depending on the severity of their vision problems.
Patients with albinism should avoid excessive exposure to the sun, especially between 10 a.m. and 2 p.m., and should wear long sleeves and pants if possible.
Most children with albinism function satisfactorily in a mainstream classroom as long as the school provides classroom assistance for their vision needs.
Hermansky-Pudlak syndrome-A rare type of albinism, most common in the Puerto Rican community, which can cause pigment changes, lung disease, intestinal disorders, and blood disorders.
However, one of the greatest health hazards for people with albinism is excessive exposure to sun without protection, which may lead to skin cancer.
Wearing opaque clothes and sunscreen with at least an SPF rating of 30, people with albinism can safely work and play outdoors even during the summer.
Genetic counseling should be considered for individuals with a family history of albinism.
Children with albinism may experience complex social problems because of their unusual appearance, especially when a member of a normally dark-skinned ethnic group has albinism.
The eyes of children with albinism may move rapidly and not focus together, and the children may have to squint, tilt their heads, and hold reading materials close in order to see.
Parents often feel that teasing and name-calling, insensitivity, and ignorance are the greatest challenges that they face with regards to their child's albinism.
The support and love of these families of children with albinism are essential to helping the children understand and accept themselves.
Support groups for the children and for their families, as well as counseling, may be useful for developing means of coping with the social effects of albinism.
Albinism: A Medical Dictionary, Bibliography, and Annotated Research Guide to Internet References.
Too White to Be Black and Too Black to Be White: Living with Albinism.
Albinism in the Family: Albinismo en la Familia.
National Organization for Albinism and Hypopigmentation (NOAH).
King, Richard A., et al. "Facts about Albinism."
International Albinism Center, University of Minnesota.
People with albinism typically have light skin, white or pale yellow hair, and light blue or gray eyes.
For example, Leber's amaurosis is an autosomal dominant trait and albinism is X-linked.
In one direction the tabby shows a tendency to melanism which culminates in complete blackness, while in the other direction there is an equally marked tendency to albinism; grey cats, which may be regarded as tabbies whose stri p es have disappeared, forming the connecting link between the tabby and the white cat.
A very ancient British breed is the black Pembroke; and when this breed tends to albinism, the ears and muzzle, and more rarely the fetlocks, remain completely black, or very dark grey, although the colour elsewhere is whitish, more or less flecked and blotched with pale grey.
Among some flowering plants, however, the character has become one of specific rank, and among animals we have in the polar bear and the Greenland hare instances where partial albinism - for in them the eyes are black and other parts may be pigmented - has also become a specific character.
In addition to complete albinism, there exist, however, various albinotic conditions in which more or less pigment may be present.
Familiar instances of this partial albinism is seen in the domestic breed of Himalayan rabbits.
Such cases are interesting as representing the last step in the graded series through which the condition of complete pigmentation passes into that of complete albinism.
Allen, that partial albinism is a condition in which pigment is reduced around definite body centres, so that unpigmented areas occur between the pigment patches or at their borders.
Some animals are wholly pigmented during the summer and autumn, but through the winter and spring they are in the condition of extreme partial albinism and become almost complete albinoes.
The condition of albinism thus assumed as a seasonal variation is never complete, for the eyes at least retain their pigmented state.
Albinism is restricted to no particular class of the animal kingdom; for partial albinism at least is known to occur in Coelentera, worms, Crustacea, Myriapoda, Coleoptera,Arachnida and fishes.
But, apart from these instances, albinism is known, according to W.
Gunn, of Edinburgh University, who has recently been investigating the subject of albinism in man, there is reason to believe that a condition of piebald albinism occurs also in Europeans (Scotsmen).
In complete human albinoes, albinism is correlated, in addition to nystagmus, with a peculiar roughness of the skin, making it harsh to the touch.
Let A stand for a pure albino and (A)N for a normal person, who nevertheless carries the character albinism (A) recessive.
Then, in the scheme below, if A b and (A)N b are two brothers who both marry normal wives N, their children N(A) in the first case will be all normal in appearance but will be carrying albinism recessive; and in the second case some will be pure normal individuals N, and some will be like the children of the first brother, i.e.
P. Mudge, "Intravascular Coagulation and Albinism, Preliminary Note," Proc. Phys.
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