The G380R mutation in the transmembrane domain of fibroblast growth factor receptor 3 (FGFR3) causes achondroplasia, the most common form of human dwarfism.
A 2-year-old boy with clinical features consistent with achondroplasia and Silver-Russell syndrome-like symptoms was found to carry a mutation in the fibroblast growth factor receptor-3 (FGFR3) gene at c.1138G > A (p.Gly380Arg) and a de novo 574 kb duplication at chromosome 7p12.1 that involved the entire growth-factor receptor bound protein 10 (GRB10) gene.
In an analysis of 19 achondroplasia families from a variety of ethnic backgrounds we confirmed the presence of the G380R mutation in 21 of 23 achondroplasia chromosomes studied.
More than 97% of achondroplasia cases are caused by one of two mutations (G1138A and G1138C) in the fibroblast growth factor receptor 3 (FGFR3) gene, which results in a specific amino acid substitution, G380R.
The assay has been tested in 50 healthy controls, 3 known patients with achondroplasia, and 5 amniotic fluids suspected of having achondroplasia and for whom we had previously determined the genotypes for the c.1138G>A mutation by PCR-RFLP.
Although 98% of ACH cases are accounted for by a single G380R substitution in the TM, a common mutation (N540K) in the TK1 region is detected in only 60-65% of HCH cases.
Meclozine also ameliorated abnormally suppressed proliferation of human chondrosarcoma (HCS-2/8) cells that were infected with lentivirus expressing constitutively active mutants of FGFR3-K650E causing thanatophoric dysplasia, FGFR3-K650M causing SADDAN, and FGFR3-G380R causing ACH.
Here we compared the ubiquitylation of either wild type or a K508A 'kinase-dead' mutant of fibroblast growth factor receptor 3 (FGFR3) with that of its naturally occurring overactive mutants, G380R as in achondroplasia, or K650E involved in thanatophoric dysplasia.
This mechanism was present in ACH children carrying the G380R mutation but also in a patient in whom no mutation could be detected in the entire coding region of the FGFR3 gene.
We report here recurrent missense mutations, in a CpG doublet of the transmembrane domain of the FGFR3 protein (G380R) in 17 sporadic cases and 6 unrelated familial forms of ACH and show that the mutant genotype segregates with the disease in these families.
Here we report the finding of recurrent missense mutations in a CpG doublet of the transmembrane domain of the FGFR3 protein (glycine substituted with arginine at residue 380, G380R) in 17 sporadic cases and 6 unrelated familial forms of achondroplasia.
The mother has achondroplasia and carries the common G1138 (G380R) mutation in the FGFR3 gene; the father has hypochondroplasia due to the C1620A (N540K) mutation in the same gene.
The fetal G1138A mutation was detectable in the two achondroplasia-affected pregnancies by the analysis of cf-DNA in maternal plasma using MALDI-TOF MS.
The vast majority of patients with achondroplasia have a G-to-A transition at position 1138 of the fibroblast growth factor receptor 3 (FGFR3) cDNA sequence, resulting in the Gly-to-Arg substitution at position 380 of the FGFR3 protein.
An exclusive paternal origin of mutations, and increased paternal age, were previously described for a different mutation (c.1138G>A) of the FGFR3 gene causing achondroplasia, as well as for mutations of the related FGFR2 gene causing Apert, Crouzon and Pfeiffer syndromes.