A brother and a sister, each of whom was born prematurely and died in early infancy, presented unusual but similar skeletal abnormalities. The following description is presented, because they may represent a previousy unrecognized syndrome. Each had been diagnosed (before death by pediatricians and radiologists and at autopsy by pathologists) as having achondroplasia. However, upon review these infants had little more than unusually short tubular bones of the arms, forearms, thighs and legs. Additional bony abnormalities included bowing of the femurs, slight hypoplasia of the lower parts of the iliac bones, and ribs which were slightly shorter than normal. The occurrence of this unusual abnormality in unlike sexed sibs suggests to us that it is a rare autosomal recessive trait. That it was mistaken for achondroplasia indicates its importance in genetic counseling.
