Genetic Disorders of Pigmentation
Normal skin pigmentation is dependent upon efficient melanin synthesis and melanosome maturation within melanocytes, melanosome transfer to neighbouring keratinocytes and melanosome degradation concomitant with keratinocyte terminal differentiation. Several hundred genes are known to modulate the pigmentation type or pattern in skin, hairs/coat and eyes in mammals, during or after development, by acting directly or indirectly on the pigment cell lineage. Among these, only a few have been found to underlie recognizable inherited pigmentation disorders. In this chapter, we review the clinical features, pathophysiology and treatment of the main inherited disorders of hypopigmentation and hyperpigmentation, including the dyschromatoses.
Keywords albinism, microphthalmia, tyrosinase, melanocyte, melanosome, dyschromatoses