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Updated: Aug 27, 2025
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Pharmacologic Induction of Epidermal Melanin and Protection Against Sunburn in a Humanized Mouse Model
Published on: September 7, 2013
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PMEL is mutated in oculocutaneous albinism.
Lama AlAbdi1,2, Muneera Alshammari3, Rana Helaby2
1Department of Zoology, College of Science, King Saud University, Riyadh, Saudi Arabia.
Human Genetics
|September 27, 2022
Summary
Oculocutaneous albinism (OCA) is a genetic disorder causing hypopigmentation. A novel PMEL gene variant was identified in a patient with OCA and Hirschsprung disease, suggesting PMEL
Area of Science:
- Genetics
- Cell Biology
- Dermatology
Background:
- Oculocutaneous albinism (OCA) comprises Mendelian disorders affecting pigmentation.
- Genetic causes for OCA are largely identified, yet some patients remain undiagnosed.
- Melanosome maturation and melanin deposition are crucial for pigmentation.
Purpose of the Study:
- To identify the genetic cause of OCA in a consanguineous family with co-occurring Hirschsprung disease.
- To investigate the role of PMEL in human pigmentation disorders.
Main Methods:
- Whole exome sequencing was performed on affected family members.
- Segregation analysis of identified variants was conducted.
- PMEL gene function was assessed based on literature review of orthologs.
Main Results:
- A homozygous loss-of-function variant in the PMEL gene was identified in the index patient.
- The patient presented with oculocutaneous albinism and Hirschsprung disease.
- PMEL is essential for melanosome maturation and melanin deposition.
Conclusions:
- The identified PMEL variant is the likely cause of OCA in this family.
- This represents the first reported human case of PMEL loss-of-function causing albinism.
- PMEL mutations should be considered in the genetic diagnosis of OCA, especially with co-occurring conditions.
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