Difference Between Albinism Melanism and Leucism

The key difference between albinism melanism and leucism is that albinism is a condition characterized by the absence of melanin while melanism is a condition characterized by lots of the pigment melanin in the skin and leucism describes a wide variety of conditions which result in the partial loss of pigmentation in an animal.

Albinism, melanism and leucism are three types of conditions associated with pigments, especially melanin present in organisms. In albinism, melanin is absent in the skin, hair or eyes. In contrast, in melanisms, there is a lot of melanin. In leucism, partial loss of pigmentation can be seen while the eyes have melanin as usual.

CONTENTS

1. Overview and Key Difference
2. What is Albinism 
3. What is Melanism 
4. What is Leucism
5. Similarities Between Albinism Melanism and Leucism
6. Side by Side Comparison – Albinism vs Melanism vs Leucism in Tabular Form
7. Summary

What is Albinism?

Albinism is a condition which is characterized by the absence of melanin in the skin, hair and eyes. Therefore, albinism differs from leucism. In albinism, melanin is absent even in the eyes of the animal. But, in leucism, melanin is present in the eyes of the animal. Albinism is a result of a defect in genes that produce or distribute melanin. Hence, animals with albinism appear as white or pale yellowish. They have very pale eyes, often pink or red in colour, as the blood vessels show through.

In humans, albinism is a congenital disorder. Moreover, it is associated with vision problems since the development of the optical system is highly dependent on the presence of melanin. Humans with albinism are more susceptible to sunburn, skin damages and skin cancers. Therefore, they need sun protection.

What is Melanism?

Melanism is the condition opposite to albinism. It is characterized by the presence of lots of melanin in the skin. Due to melanism, body parts are morphologically visible as dark. It happens as a result of unusual or high deposition of melanin. Similar to albinism, melanism is also hereditary. It happens due to the mutation of different genes.

Melanism can be adaptive melanism or industrial melanism. Adaptive melanism is related to the process of adaptation. Industrial melanism is an evolutionary effect that is related to industrial pollution. Animals that show adaptive and industrial melanism are better camouflaged. Melanism does not exist in humans, as seen in other animals.

What is Leucism?

Leucism is a condition which describes a partial loss of pigmentation. It gives the animal a pale or washed out appearance. They can have white or patchily coloured skin, hair or feathers. However, in leucism, pigment cells in the eyes are not affected. Hence, animals, especially birds with leucism, have black colour eyes.

Leucism can be seen in a number of animal species. But it does not exist in humans. Leucism is a genetic peculiarity due to a gene which is recessive in most cases.

What are the Similarities Between Albinism Melanism and Leucism?

• All three conditions are inherited disorders.
• They are related to pigmentation.
• They occur as a result of genetic mutation.

What is the Difference Between Albinism Melanism and Leucism?

Albinism is a genetic condition that reduces the amount of melanin pigment formed in the skin, hair and/or eyes. Melanism is a condition in which an increase of dark pigment takes place, resulting in a blackish appearance. Leucism, on the other hand, is a condition in which only a partial loss of pigmentation takes place, resulting in white or patchily coloured skin, hair, or feathers. So, this is the key difference between albinism melanism and leucism. Albinism is associated with the absence of melanin while animals with melanism have a high amount of melanin granules in the skin, hair, and eyes. Animals with leucism show partial loss of pigmentation. However, pigment cells in the eyes are not affected.

Below infographic summarizes the difference between albinism melanism and leucism.

Summary – Albinism Melanism vs Leucism

Albinism, melanism and leucism are three types of genetic disorders associated with pigmentation. Albinism is a condition associated with the absence of melanin pigment in the skin, hair and/or eyes. Melanism is the condition associated with a lot of melanin production. Leucism, on the other hand, is the partial loss of pigmentation in skin, hair, or feathers. Thus, this is the difference between albinism melanism and leucism.

Reference:

1. Kivi, Rose. “Albinism: Causes, Types, and Symptoms.” Healthline, Healthline Media, 17 Sept. 2018, Available here.
2. “Melanism.” Wikipedia, Wikimedia Foundation, 14 Aug. 2020, Available here.
3. “Leucism.” Wikipedia, Wikimedia Foundation, 6 Sept. 2020, Available here.

Image Courtesy:

1. “Albinisitic man portrait” By The original uploader was Muntuwandi at English Wikipedia. – Transferred from en.wikipedia to Commons (CC BY-SA 3.0) via Commons Wikimedia
2. “Cavia porcellus-Licorice” By No machine-readable author provided. Miia "Myrtti" Ranta assumed (based on copyright claims). – No machine-readable source provided. Own work assumed (based on copyright claims) (CC BY-SA 3.0) via Commons Wikimedia
3. “White Lion” By Stano Novak – Own work (CC BY 2.5) via Commons Wikimedia