Two CASES OF WAARDENBURG SYNDROME TYPE 1

IMPLICATIONS FOR GENETIC COUNSELING

Abstract

Waardenburg syndrome type 1, caused by a congenital ectodermal germ layer defect with an autosomal dominant pattern of inheritance and variable phenotypic expressivity, consists of 6 major characteristics : dystopia canthorum, broad nasal root, hypertrichosis of the medial eyebrow, heterochromia irides, white fore-lock, and congenital sensory hearing loss. These stigmata may be present in any combination and degree. We report two cases of Waardenburg syndrome type 1. The first case was a one-month old girl with unilateral deafness identified through early neonatal hearing screening. The second case was the child's father, who did not have any hearing loss. The degree of hearing loss is variable within and between families. The implications of this finding for genetic counseling in families with this syndrome are discussed.