Heterozygous (FGFR3<sup>ACH/+</sup>) and homozygous (FGFR3<sup>ACH/ACH</sup>) mice expressing human FGFR3<sup>G380R</sup> recapitulate the phenotypes observed in ACH patients, including growth retardation, disproportionate shortening of the limbs, round head, mid-face hypoplasia at birth, and kyphosis progression during postnatal development.