Trisomies

Our cells usually have 23 pairs of chromosomes. Trisomy is the word used to describe the presence of an extra chromosome in the cells. Trisomies are named based on which chromosome has the extra copy, so a person with trisomy 21 has an extra copy of chromosome 21. Trisomies are not typically inherited, and while women of any age can have a child with a trisomy, the likelihood increases with mother's age.1 People with trisomies are not all the same, but the common trisomies are associated with birth defects, intellectual disability and a range of health problems. 

Trisomy 18

Trisomy 18 happens in about 1 in 5,000 live births.2 It occurs when cells have an extra copy of chromosome 18 and is typically not inherited. People with trisomy 18 have serious differences in physical and cognitive development. Although women of any age can have a child with trisomy 18, the likelihood increases with mother’s age.For more detailed information about trisomy 18, including pregnancy management, health care guidelines, advocacy and support for families:

Chromosome 18 Registry and Research Societywww.chromosome18.org

Trisomy 18 Foundationwww.trisomy18.org

Learn more about the Harmony prenatal test for Trisomy 18.

SOFT (Support Organization for Trisomy 18, 13 and other Related Disorders)http://trisomy.org/

NIH Genetics Home Referencehttps://ghr.nlm.nih.gov/condition/trisomy-18

Learn more about the Harmony prenatal test for Trisomy 18.

Trisomy 13

Trisomy 13 happens in about 1 in 16,000 live births.3 It occurs when cells have an extra copy of chromosome 13, and is typically not inherited. People with trisomy 13 have serious differences in physical and cognitive development. Although women of any age can have a child with trisomy 13, the likelihood increases with mother’s age.

 

For more detailed information about trisomy 13, including pregnancy management, health care guidelines, advocacy and support for families:

SOFT (Support Organization for Trisomy 18, 13 and other Related Disorders)

http://trisomy.org/

NIH Genetics Home Reference
https://ghr.nlm.nih.gov/condition/trisomy-13

Learn more about the Harmony prenatal test for Trisomy 13.

1.        U.S. National Library of Medicine. Genetics Home Reference. Down Syndrome. https://ghr.nlm.nih.gov/condition/down-syndrome. Accessed April 25, 2018.

2.        2. U.S. National Library of Medicine. Genetics Home Reference. Trisomy 18. https://ghr.nlm.nih.gov/condition/trisomy-18. Accessed April 25, 2018.

3.        U.S. National Library of Medicine. Genetics Home Reference. Trisomy 13. https://ghr.nlm.nih.gov/condition/trisomy-13. Accessed April 25, 2018.

References

1.        U.S. National Library of Medicine. Genetics Home Reference. Down Syndrome. https://ghr.nlm.nih.gov/condition/down-syndrome. Accessed April 25, 2018.

2.        2. U.S. National Library of Medicine. Genetics Home Reference. Trisomy 18. https://ghr.nlm.nih.gov/condition/trisomy-18. Accessed April 25, 2018.

3.        U.S. National Library of Medicine. Genetics Home Reference. Trisomy 13. https://ghr.nlm.nih.gov/condition/trisomy-13. Accessed April 25, 2018.