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Phenotypic and microscopic description of a new case of Ermine phenotype
Yuri A Zarate1, M Cristina Pacheco, Kevin E Bove
1Cincinnati Children's Hospital Medical Center, Division of Human Genetics, Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio 45229, USA.
Abstract:
We describe a new case of Ermine phenotype. The patient had the striking pattern of skin and hair involvement that characterize the condition, global developmental delay, growth retardation, microcephaly, and bilateral hearing loss. Results of extensive workup for several other neurologic, metabolic, mitochondrial, genetic and chromosomal conditions were normal. Microscopic examination demonstrated normal numbers of melanocytes and variable amounts of pigment depending on the degree of pigmentation in the region biopsied. Ultrastructure of melanosomes was abnormal suggesting a defect in melanin synthesis. Ermine phenotype has a distinct clinical presentation compared to other syndromes associated with abnormal pigment and deafness. Therefore, this should be included as an independent condition in the differential diagnosis. Additional phenotypic and pathologic descriptions are needed to better define this condition clinically, pathologically, and genetically.
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