Achromasia · What Is It, Causes, Diagnosis, Treatment, and More

Achromasia results from inheriting a mutation in one of the several genes that are responsible for the production of melanin.  

Oculocutaneous albinism (OCA) is the most common type of achromasia, and it occurs when an individual receives two copies of a mutated gene, one copy from each parent, called autosomal recessive inheritance. Inheritance of these mutations is a result of a mutation in one of the eight OCA genes, such as TYR, TYRP1, OCA2, among others. Mutations in OCA genes can cause decreased pigmentation in the skin, eyes, and hair, as well as the characteristic visual problems. An individual’s particular level of pigmentation depends on the specific OCA gene that is mutated.  

Ocular albinism type 1 is another common type of ocular albinism, although it occurs much less frequently than OCA and mainly causes visual problems. This type of achromasia is a recessive X-linked disorder: in female offspring, both inherited X chromosomes must have the mutation for the infant to express the disorder, whereas in male offspring, only the single X chromosome must contain the mutation for the infant to express the disorder. Accordingly, ocular albinism type 1 is most often passed down from mother to son and occurs most frequently in males.  

Finally, achromasia can occur alongside various rare hereditary disorders, such as Hermansky-Pudlak syndrome or Chiadek Higashi syndrome. Hermansky-Pudlak is a disorder that results in OCA, bleeding problems, and possible lung and colon issues. Chiadek Higashi syndrome is a rare immune disorder that often presents in childhood with OCA, immunodeficiency, and bleeding and bruising problems.  

Accordingly, the common signs and symptoms of achromasia tend to affect the hair, skin, and eyes. Hair color of individuals with achromasia can range from white to brown; however, those of African or Asian descent may have yellowish or reddish hair. Hair color may darken with age but varies from person to person. Eyelashes and eyebrows are often very similar in hue to the individual’s hair color and are typically pale. Eye color can range from light blue to brown and, like hair color, can also darken with age. Skin coloring for those with achromasia ranges from white to brown, but it’s a less distinct sign of the condition since an individual with achromasia can have nearly the same skin tone as that of a parent or sibling who does not have achromasia. Individuals with achromasia are more prone to the formation of freckles, moles, and sunburns upon sun exposure. This increased sensitivity to sunlight lends to an increased risk of developing skin cancer.  

Though hair, eyes, and skin are the most recognizable ways to identify achromasia, visual impairment is an additional key feature of achromasia. Visual impairments that may arise include an inability of both eyes to focus on the same point or move in unison, extreme nearsightedness, extreme farsightedness, or rapid and involuntary back and forth movements of the eye called nystagmus. Other common visual difficulties include sensitivity to light, abnormal curvature of the front of the eye causing blurred vision, abnormal retina development causing reduced vision, poor depth perception, and, in some cases, legal blindness.  

Diagnosis of achromasia is primarily based on a thorough review of medical history, family history, and a physical examination. The physical examination often includes an examination of the hair, skin, and eyes. Often, an individual’s pigmentation may be compared to that of their family members. Genetic testing and consultation can help to determine an individual’s specific type of albinism.  

Since achromasia is an inherited disorder, it cannot be cured, so treatment is focused on monitoring and managing symptoms, as well as preventing further complications. A treatment regimen may include an annual eye and skin exam to monitor for potential issues, such as skin cancer. Individuals with achromasia may need visual aids and visual acuity support. Other lifestyle interventions include wearing sunscreen, protective clothing, and eye protection, especially while outside. It is also suggested that individuals with achromasia avoid long periods of sun exposure.