Comparison of clinical, radiological and molecular findings in Korean infants and children with achondroplasia and hypochondroplasia.
Achondroplasia (ACH) and hypochondroplasia (HCH) share clinical features characterized by disproportionate short stature with rhizomelic shortening of the limbs. In an attempt to clarify genotype-phenotype correlation in ACH and HCH, we investigated the presence of the previously identified mutations of FGFR3 in 26 patients with ACH- or HCH-mimicking features and compared clinical and radiographic findings between the two groups. Using genomic DNA sequencing and RFLP analysis, G380R, an ACH-specific mutation, and N540K, an HCH-specific mutation, were detected in 13 patients (50%) and five patients (19%), respectively. No mutations of FGFR3 were detected in eight patients (31%). No remarkable clinical or radiological differences were evident among the ACH infants and children with G380R, the HCH patients with N540K, and the patients without verified mutations. These results suggest that genotype-based diagnosis needs to precede proper genetic counseling for patients with ACH or HCH, which show very similar clinical and radiological features.
Shin
Young-Lim
YL
Department of Pediatrics, Asan Institute for Life Sciences, University of Ulsan College of Medicine, Seoul, Korea.
Choi
Jin-Ho
JH
Kim
Gu-Hwan
GH
Yoo
Han-Wook
HW
D000015:Abnormalities, Multiple / Q000000981:diagnostic imaging / Q000235:genetics* / Q000503:physiopathology; D000130:Achondroplasia / Q000000981:diagnostic imaging / Q000235:genetics* / Q000503:physiopathology; D001842:Bone and Bones / Q000000981:diagnostic imaging; D002648:Child; D002675:Child, Preschool; D005260:Female; D015894:Genome, Human; D005838:Genotype; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007723:Korea; D008297:Male; D020125:Mutation, Missense; D010641:Phenotype; D011859:Radiography; D051498:Receptor, Fibroblast Growth Factor, Type 3 / Q000235:genetics*; D017422:Sequence Analysis, DNA
C496365:FGFR3 protein, human; D051498:Receptor, Fibroblast Growth Factor, Type 3