limb malformations

Malformations in the SOX9 gene can result in a variety of syndromes including Pierre Robin Syndrome, Campomelic Dysplasia, and Acampomelic Campomelic Dysplasia. In Greek, Campomelic means “bent limb,” which is a common symptom of Campomelic Dysplasia. Individuals born without bowed limbs are said to have Acampomelic Dysplasia. Both syndromes involve skeletal and reproductive malformations and are life-threatening in newborns. Malformations in the Hh signaling pathway can cause Holoprosencephaly, Microphthalamia with Coloboma, and Schizencephaly. Holoprosencephaly is an abnormality in brain development when the prosencephalon does not divide into the left and right hemispheres. Microphthalmia occurs when one or both eyeballs is abnormally small. People with Microphthalmia often have Coloboma, an anatomic abnormality in which pieces of tissue are missing from the eye. Finally, Schizencephaly is a rare birth defect that causes clefts in the cerebral hemispheres of the brain.