title: Long-term follow-up study for a patient with Floating-Harbor syndrome due to a hotspot SRCAP mutation.
abstract: Floating-Harbor syndrome (FHS) is a rare autosomal dominant disorder characterized by short stature, skeletal malformations, speech delay, and dysmorphic facial appearance. Recently, mutations in SRCAP encoding a coactivator for cAMP-response element binding protein (CREB)-binding protein have been identified in small number of patients with FHS. Here, we report on long-term follow-up data of a male patient with a SRCAP mutation. The patient presented with mild hypothyroidism and renal hypouricemia, in addition to several FHS-compatible features including growth impairment, cognitive disability, facial dysmorphisms, and hypertension. He showed delayed bone age from infancy to 9 years of age and markedly accelerated bone age with the formation of cone-shaped epiphyses and early epiphysial fusions after the onset of puberty. His pubertal sexual development was almost age appropriate. Two-year treatment with growth hormone (GH) did not significantly improve the growth velocity. Molecular analysis identified a de novo heterozygous nonsense mutation (p.R2444X) in the last exon of SRCAP, which has been most common mutation detected in patients from other ethnic groups. These results indicate that perturbed skeletal maturation from infancy through adolescence is a characteristic feature in patients with SRCAP mutations. Furthermore, our data imply that GH therapy exerted only a marginal effect on the growth of this patient, and that renal hypouricemia may be a novel complication of FHS.
authors.affiliation: Department of Molecular Endocrinology, National Research Institute for Child Health and Development, Tokyo, Japan; Division of Pediatrics, Department of Homeostatic Regulation and Development, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Nagasaki
authors.forename: Tadashi
authors.initials: T
authors.lastname: Asami
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Sato
authors.forename: Yohei
authors.initials: Y
authors.lastname: Ogawa
authors.forename: Toru
authors.initials: T
authors.lastname: Kikuchi
authors.forename: Akihiko
authors.initials: A
authors.lastname: Saitoh
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Ogata
authors.forename: Maki
authors.initials: M
authors.lastname: Fukami
mesh_terms: D000015:Abnormalities, Multiple / Q000175:diagnosis* / Q000235:genetics*; D000251:Adenosine Triphosphatases / Q000235:genetics*; D002648:Child; D019465:Craniofacial Abnormalities / Q000175:diagnosis* / Q000235:genetics*; D004252:DNA Mutational Analysis; D005500:Follow-Up Studies; D006130:Growth Disorders / Q000175:diagnosis* / Q000235:genetics*; D006345:Heart Septal Defects, Ventricular / Q000175:diagnosis* / Q000235:genetics*; D006801:Humans; D008297:Male; D009154:Mutation; D010641:Phenotype
chemical_list: D000251:Adenosine Triphosphatases; C119652:SRCAP protein, human
keywords: Floating-Harbor syndrome; SRCAP; growth; mutation; puberty; short stature