ABSTRACT
Thanatophoric dysplasia [TD] is an osteochondrodysplasia always lethal in the neonatal period. The vast majority of cases are due to de novo mutations. It is divided into two types: a short curved femur characterizes type 1, while a straighter femur with clover leaf skull characterizes type 2. In thanatophoric dysplasia the limbs are very short. The rib cage is small. The vertebral bodies of the spine are greatly reduced in height with wide spaces between them. Autosomal dominant mutations in the fibroblast growth factor receptor 3 gene [FGFR3], which has been mapped to chromosome band 4p16.3, results in both subtypes. This condition has characteristic sonographic features that suggest the diagnosis prenatally. Thanatophoric fetuses usually die within the first 48 hours of life from pulmonary hypoplasia caused by a narrow thorax, leading to respiratory insufficiency. We reported twin dizygote cases of type 1 TD with similar findings adjusting with TD for the first time, along with a short review of the available literature