Radiographic and genetic diagnosis of sporadic hypochondroplasia early in the neonatal period.
Hypochondroplasia is an autosomal dominant skeletal dysplasia expressing postnatal onset of short stature with mild rhizomelic shortening of the limbs. This manifestation leads to restricted prenatal diagnosis of the disorder. We report here on a sporadic case of a hypochondroplastic baby, whose prenatal sonographic measurements were serially recorded from 19 weeks of gestation. Mild shortening of the limbs became manifest after 26 weeks of gestation. Biparietal diameter was within the normal range throughout gestation. Both parents were of average stature. A tentative diagnosis of a nonlethal short-limb skeletal dysplasia was made. At birth, the clinical manifestations of the neonate were not characteristic, but the radiographic features raised the possibility of hypochondroplasia. Molecular analyses revealed a C to G mutation at nucleotide 1659 of the fibroblast growth factor receptor 3 (FGFR3) gene, a common mutation in hypochondroplasia.
Kataoka
Soromon
S
Department of Obstetrics and Gynecology, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
Sawai
Hideaki
H
Yamada
Hideto
H
Kanazawa
Nozomi
N
Koyama
Koji
K
Nishimura
Gen
G
Morikawa
Mamoru
M
Sakuragi
Noriaki
N
Minakami
Hisanori
H
D000328:Adult; D003937:Diagnosis, Differential; D005260:Female; D005820:Genetic Testing; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D010009:Osteochondrodysplasias / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000196:embryology / Q000235:genetics; D011247:Pregnancy; D011263:Pregnancy Trimester, Third; D011296:Prenatal Diagnosis; D011505:Protein-Tyrosine Kinases; D011859:Radiography; D051498:Receptor, Fibroblast Growth Factor, Type 3; D017468:Receptors, Fibroblast Growth Factor / Q000235:genetics
D017468:Receptors, Fibroblast Growth Factor; C496365:FGFR3 protein, human; D011505:Protein-Tyrosine Kinases; D051498:Receptor, Fibroblast Growth Factor, Type 3