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Trisomy 13

(Patau Syndrome; Trisomy D)

By

Nina N. Powell-Hamilton

, MD, Sidney Kimmel Medical College at Thomas Jefferson University

Reviewed/Revised Nov 2023
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Topic Resources

Trisomy 13 is a chromosomal disorder caused by an extra chromosome 13 that results in severe intellectual disability and physical abnormalities.

  • Trisomy 13 is caused by an extra chromosome 13.

  • Infants are typically small and often have major brain, eye, face, and heart defects.

  • Tests can be done before or after birth to confirm the diagnosis.

  • There is no cure for trisomy 13.

An extra chromosome, making three of the same chromosome (instead of the normal two), is called trisomy. Children who have trisomy 13 have a third chromosome 13.

Trisomy 13 occurs in about 2 out of 10,000 pregnancies. The extra chromosome usually comes from the mother. The risk of trisomy 13 increases with the mother's age.

Symptoms of Trisomy 13

In the womb, affected fetuses are typically not very active. The amount of amniotic fluid may be too much or too little.

Physical abnormalities

The ears are abnormally shaped and usually low-set. Defects in the scalp and openings in the skin are common. Loose folds of skin often are present over the back of the neck.

Cleft Lip and Cleft Palate: Defects of the Face

Cleft Lip and Cleft Palate: Defects of the Face

Other abnormalities

Diagnosis of Trisomy 13

  • Before birth, ultrasonography of the fetus or blood tests of the mother

  • Before birth, chorionic villus sampling, amniocentesis, or both

  • After birth, the appearance of the infant and blood tests of the infant

Before birth, trisomy 13 may be suspected based on findings detected during an ultrasound of the fetus. Doctors also can do a test to find deoxyribonucleic acid (DNA) from the fetus in the mother's blood and use this DNA to determine an increased risk of trisomy 13. This test is called noninvasive prenatal screening (NIPS) or cell-free fetal DNA analysis.

After birth, the infant's physical appearance may suggest the diagnosis of trisomy 13. To confirm the diagnosis, the infant's chromosomes are analyzed using a blood test.

Treatment of Trisomy 13

  • Support for the family

There is no cure for trisomy 13.

It is recommended that family members seek support.

Prognosis for Trisomy 13

In the past, most infants died soon after birth. However, in recent times, some infants have been living longer.

More Information

The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

NOTE: This is the Consumer Version. DOCTORS: VIEW PROFESSIONAL VERSION
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