Abstract
Floating-Harbor syndrome is a sporadic, autosomal dominantly-inherited, malformation syndrome characterized by typical craniofacial findings, proportional short stature, significantly delayed bone age, delayed expressive language, delayed speech, and normal head circumference. It is caused by heterozygous mutations in the SNF2-associated CBP activator protein gene (SRCAP) located on chromosome 16. Here, we report a 9.3 years old male patient who presented to the pediatric genetics outpatient clinic with retardation in early developmental stages, dysmorphic facial features, and short stature. A triangular face, short filtrum, posteriorly rotated ear, deep-set eyes, bulbous nose, prominent columella, and low hairline are unique facial features in the syndrome. He also has short stature, significant retardation in bone age, and retardation in expressive language, all suggesting Floating-Harbor syndrome. The diagnosis was confirmed through molecular testing which revealed a heterozygous c.7330C>T p.(Arg2444Ter) pathogenic variant in exon 34, of the SRCAP gene. Floating-Harbor syndrome should be remembered in the differential diagnosis of patients evaluated for short stature and learning disability with its unique facial features. By reporting a new case of Floating-Harbor syndrome our aim was to expand the clinical and molecular spectrum in this rare syndrome and increase diagnostic awareness for pediatric endocrinology practitioners.
Keywords: Floating-Harbor syndrome, SRCAP gene, short stature
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