trisomy 21


Examples of trisomy 21 in a Sentence

Recent Examples on the Web This individual, thought to be the oldest record of Down syndrome, was also examined in the new study and confirmed to have had trisomy 21. Catherine Duncan, Smithsonian Magazine, 27 Feb. 2024 For example, trisomy 21, the most common form, also known as Down syndrome, occurs when a baby is born with three No. 21 chromosomes. Rick Mauch, Fort Worth Star-Telegram, 24 Jan. 2024 The most common type of Down syndrome is trisomy 21. Ashlyn Messier, Fox News, 8 Oct. 2023 Kayleigh Williamson will be wearing bib number 321 at #Boston127—a number representing the trisomy 21 in the Down syndrome community. Shannon Larson,, 14 Apr. 2023 People with Down syndrome, or trisomy 21, a genetic condition caused by an extra copy of human chromosome 21, experienced a remarkable increase in life expectancy during the 20th century. Joaquin Espinosa, The Conversation, 5 June 2023 One condition that could be affected is Down syndrome or trisomy 21, which occurs when a person carries an extra copy (partial or complete) of chromosome 21. Joshua Rapp Learn, Discover Magazine, 8 May 2023 Lulu was born with trisomy 21, or Down syndrome, the most common chromosomal anomaly diagnosed in the United States; the condition, which affects about six thousand American babies each year, causes conspicuous delays in mental and physical development. Eren Orbey, The New Yorker, 18 Aug. 2020 Ultrasound in Obstetrics & Gynecology, 2013; DOI:10.1002/uog.12504 First-trimester contingent screening for trisomy 21 by biomarkers and maternal blood cell-free DNA testing. Razib Khan, Discover Magazine, 9 June 2013

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'trisomy 21.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


from the occurrence of trisomy in chromosome 21 of persons with Down syndrome

First Known Use

1961, in the meaning defined above

Time Traveler
The first known use of trisomy 21 was in 1961

Dictionary Entries Near trisomy 21

Cite this Entry

“Trisomy 21.” Dictionary, Merriam-Webster, Accessed 16 Jun. 2024.

Medical Definition

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