Trisomy 18
By: Joe Salerno
Overview
Trisomy 18 is a genetic syndrome that causes specific birth defects and causes profound mental retardation. It is caused by the presence of an extra chromosome 18 in some or all of the cells of the body. Babies with the condition usually do not survive past their first several months, but if they do their body has some restrictions to it. Trisomy 18 occurs while at the stage of embryo/fetus.
Inherited
Research
Symptoms
the typical features include:
- intrauterine growth retardation
- craniofacial features such as abnormalities of the jaw, skull, ears, and neck
- clenched fists with overriding fingers
- small fingernails
- short sternum
- club feet
- heart defects
- kidney defects
- neurodevelopmental delays
Tests- First-Trimester Screening for Trisomy 18- Disorder Testing--- No treatments
Down syndrome and trisomies 13 and 18 are chromosomal disorders that cause mental retardation and birth defects. Trisomy 18 (having an extra chromosome No. 18) is more a more severe disorder causing profound mental retardation and severe birth defects in many organ systems. Few babies born with trisomy 18 survive more than a few months. Anyone can have a baby with chromosome abnormalities; however, the chance increases with the mother's age. Christiana Care is the only health system in Delaware that offers first-trimester screening and the ability for immediate prenatal diagnostic testing for Trisomy 18 (Edwards' syndrome). The screening is noninvasive and poses no risk to the mother or baby. In fact, the American College of Obstetricians and Gynecologists has endorsed first-trimester screening for chromosomal disorders.