Why Albinism Happens:

Albinism is a genetic disorder, meaning that it is governed by genes. Genetic disorders are inherited from parents and are present from the moment of conception throughout the entire life of the sufferer. The genes responsible for albinism are located on several different chromosomes, including the X chromosome.

This is a punnet square, which diagrams how genes are inherited. Each parent contributes one side of the square and they are crossed, like a multiplication table, to find the possible outcomes of a child produced by the two parents. In the case of most traits in humans, there are two types of traits, either dominant(T) or recessive(t). The dominant gene's information will be used over the recessive gene. In other words, if a child ends up with the genotype (genes) Tt they will have the same traits as if they had TT. However, if two people with Tt have a child, they have a one in four chance of having a child that is tt. In this case, the child will show the effects that the t gene has on them. In the case of many disorders, the information contained within the recessive (t) gene is responsible for the sufferer's symptoms.

The information described above is found encoded in chromosomes, tiny balls of DNA, the substance that contains all the information that makes up a human being. Nearly all humans have 46 chromosomes, which hold their entire genetic makeup. The genes that cause albinism in certain conditions are scattered about the 46 chromosomes, which are known by number except for the X and Y. The Y chromosome is special because only men have it. It determines the sex of humans. Women in the place of the Y chromosome have a second X. These chromosomes get their names from their shape,the Y being an incomplete copy of the X. This means that often men do not have two copies of every trait, the ones that are missing from the Y chromosome are not present, so they recieve only the genetic information on their one X chromosome.

All of this is important to understand because all of the protiens created in the human body are encoded on its chromosomes. Protiens account for nearly every trait that can be observed in humans, including skin tone. When the chromosomes involved in the formation of melanin(11,15,13,9,10 and X), which is responsible for skin pigment in humans, are damaged or imcomplete, then the proper protiens may not form and the person will be albino.

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