How Does Ocular Albinism Affect The Eyes & What Triggers It?

Ocular albinism is a genetic condition occurring due to the defect in the genetic material of the individual that is DNA. Ocular albinism has been classified into many groups and labeled as types of it out of which type one is the most common form of ocular albinism found individually as well as in the form of syndromes.

Type 1 ocular albinism is associated with a genetic mutation of the GPR143 gene located on the chromosome of the DNA.^[1] This gene is an essential part of the pathway required to form melanin. The proteinaceous enzyme known as tyrosine kinase which is responsible for the formation of melanin gets the coding related directions from the GPR143 gene which becomes defective in the mutated GPR143 gene and hence the function of the pathway is decreased.

How Does Ocular Albinism Affect The Eyes?

The mutation of genes of ocular albinism would not necessarily result in a structural and functional defect of the eye but it depends upon the amount of mutation as well as severity also. When there is a defect of melanin production in the body it is seen as a loss of pigmentation of the body parts like skin, hair but in ocular albinism, there is normal pigmentation of the skin hair and only the eye is affected. The iris of the eye becomes depigmented and there is a difference in the color with the other individuals.

There can be foveal hypoplasia or transillumination defects in the eye.^[2] In foveal hypoplasia, there is decreased growth of the most important part of the retina that is macula which results in defective visual acuity. In transillumination defects, there is the illumination of the retina after the light crosses from within the iris and it creates multiple images formation on the retina causing diplopia to the individual. Such a defect can also be related to photophobia due to excessive illumination of the eye. In a rare case, it can also be associated with optic nerve defects resulting in nystagmus which can be physically seen upon the clinical examination of the eye.

What Triggers Ocular Albinism?

Ocular albinism can be triggered by various types of mutations like deletions, inversions, frameshift mutations etc. The mutation is a phenomenon that creates a defect in the DNA and hinders the normal function of the DNA. It stops the further enzymatic function to create the relevant protein from the defective gene. Being a genetic phenomenon, it can occur naturally with time over the generations when the normal changes in the DNA become accumulated and can create a different type of mutation affecting the GPR143 gene. It can also occur due to the radiation and other causes that can alter the DNA and create mutations in the germ cells of the individual and it can be transferred over the generations with the help of haploid progenitor cells for e.g.: sperms via the process of reproduction.

Conclusion

Ocular albinism is a hereditary condition inherited from the parents or caused due to the mutation causing factors in the earlier generations. There are only a few of the trigger factors for albinism to kickoff especially in the eye termed as ocular albinism and has been mentioned in this article.

It is not necessary that albinism always affects the eye and many times eye is spared from the syndrome. Even if the ocular involvement is seen in albinism specifically termed as ocular or oculocutaneous albinism then also it can only be physical abnormality and with no functional relevance to it. It is most commonly associated with a decrease in visual acuity of the eye as the primary functional disability which can occur from a variety of factors like foveal hypoplasia, optic nerve defects, trance illumination defects of the iris, etc.

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How Does Ocular Albinism Affect The Eyes & What Triggers It?