Dwarfism in Dexter cattle is not caused by the mutations in FGFR3 responsible for achondroplasia in humans.
Dexter cattle carry a genetic defect causing a dwarf phenotype in the heterozygotes (Dx+/-), while homozygotes (Dx+/+) are stillborn with extreme shortening of limbs and gross craniofacial defects and are described as 'bulldog' calves. The heterozygous phenotype has been likened to achondroplastic dwarfism in humans (ACH), which has recently been shown to be the result of mutations in the transmembrane region of the fibroblast growth factor receptor 3 (FGFR3) gene. We have sequenced the transmembrane region of bovine FGFR3 from normal Dexter cattle (Dx-/-) and bulldog calves (Dx+/+). The sequence from both is identical and therefore excludes mutations in the trans-membrane region of FGFR3 as the cause of Dexter dwarfism.
Usha
A P
AP
Roslin Institute (Edinburgh), Midllothian, Scottland.
Lester
D H
DH
Williams
J L
JL
D000130:Achondroplasia / Q000235:genetics*; D000818:Animals; D001483:Base Sequence; D002417:Cattle; D002418:Cattle Diseases / Q000235:genetics*; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D004392:Dwarfism / Q000235:genetics / Q000662:veterinary*; D005260:Female; D006801:Humans; D008969:Molecular Sequence Data; D009154:Mutation; D011505:Protein-Tyrosine Kinases; D051498:Receptor, Fibroblast Growth Factor, Type 3; D017468:Receptors, Fibroblast Growth Factor / Q000235:genetics*; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid
D018076:DNA, Complementary; D017468:Receptors, Fibroblast Growth Factor; C496365:FGFR3 protein, human; D011505:Protein-Tyrosine Kinases; D051498:Receptor, Fibroblast Growth Factor, Type 3