trisomy

American  

[trahy-soh-mee] / ˈtraɪ soʊ mi /

noun

Pathology.

1. an abnormality characterized by the presence of an additional chromosome to the normal diploid number.

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trisomy British  

/ traɪˈsəʊmɪk, ˈtraɪsəʊmɪ /

noun

1. the condition of having one chromosome of the set represented three times in an otherwise diploid organism, cell, etc. Trisomy of chromosome 21 results in Down's syndrome

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trisomy Scientific  

/ trī-sō′mē,trī′sō′- /

1. The condition of having three copies of a given chromosome in each body cell rather than the normal number of two.

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Other Word Forms

Derived Forms

• trisomic
  adjective

Etymology

Origin of trisomy

First recorded in 1925–30; tri- + -some ³ + -y ³

Example Sentences

A social media search led her to Dr. John Carey, a professor emeritus of pediatrics at the University of Utah, who has devoted his life to helping families dealing with trisomy 18.

From New York Times • Mar. 28, 2024

The researchers also found lower levels of Snhg11 in the same types of tissues from human postmortem brains with trisomy 21, indicating the relevance for the human cases.

From Science Daily • Feb. 27, 2024

But tests confirmed late last month that the baby she was carrying had a condition called trisomy 18, an extra chromosome that made it likely the baby would die in utero or shortly after birth.

From Seattle Times • Dec. 12, 2023

It also gives a doctor an opportunity to look for 11 rare conditions which could be life-threatening to mom, the baby, or both — like the genetic disorder trisomy 18.

From Salon • Dec. 12, 2023

Kate Cox, who is 20 weeks pregnant with her third child, learned that her child had full trisomy 18, a genetic condition that is almost always fatal in utero or the first year after birth.

From Slate • Dec. 8, 2023