Tietz Syndrome
Tietz syndrome is a genetic hypopigmentation and deafness syndrome characterized by congenital profound bilateral sensorineural hearing loss and generalized albino-like hypopigmentation of skin, eyes and hair.
Epidemiology
Tietz syndrome has been reported in 7 families to date.
Clinical description
Affected cases have a pale skin, blue eyes and light blond to white hair with white eyebrows and eyelashes. They gradually gain some pigmentation often as freckles on sun-exposed areas. Hearing loss is always bilateral, congenital, sensorineural and profound. Psychomotor development is normal.
Etiology
The syndrome is due to a missense mutation or in-frame deletion of one amino acid in the basic domain of the MITF (3p14-p13) gene, coding a basic helix-loop-helix (bHLH) leucine zipper transcription factor, regulating melanocyte development and the biosynthetic melanin pathway. However, these types of mutations give rise to variable phenotype, ranging from Tietz syndrome to Waardenburg syndrome type 2 (see this term), with possible interactions with modifier loci.
Genetic counseling
Tietz syndrome is an autosomal dominant syndrome. Genetic counseling is recommended.