a lethal dwarfism characterized by micromelia, bowed long bones, enlarged head, flattened vertebral bodies, and muscular hypotonia; lack of pulmonary ventilation causes respiratory difficulties with cyanosis leading to death within the first few hours or days after birth; inherited as a new autosomal dominant, caused by a mutation in the FGFR3 gene.
thanatophoric dwarfismthanatos, Greek, death, phoric, bearing, Chondrodysplasia punctata dwarfism of Conradi-Hünermann An AD form of dwarfism with a 2:1 ♂:♀ ratio, in which the infants are stillborn or die in early infancy Clinical Hydrocephaly, megalocephaly with frontal bossing, chondrodystrophy, narrow thorax with respiratory difficulties, congenital heart disease, hypotonia and hyporeflexia–floppy infant, hypertelorism, 'cloverleaf' skull, saddle nose, marked skeletal abnormalities with shortened deformed 'telephone receiver' long bones, affecting the epiphysis, causing micromelia, altered feet, lenticular opacity, shortened extremities with curved fingers, H or U-shaped vertebrae and pulmonary hypoplasia result in short postnatal survival
Dwarfism caused by generalized failure of endochondral bone formation. It is characterized by a large head, a prominent forehead, hypertelorism, a saddle nose, and short limbs extending straight out from the trunk. Most of these infants die soon after birth.