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

• trisomic adjective

Etymology

Origin of trisomy

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

Example Sentences

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 Down syndrome — also known as trisomy 21 — is a remarkably variable disease.

From New York Times • Feb. 20, 2024

They screen for chromosomal disorders such as trisomy 13 and 18, which often end in miscarriage or stillbirth, Down syndrome and extra or missing copies of sex chromosomes.

From Seattle Times • Feb. 12, 2024

Carrying a pregnancy with trisomy 18 to term is associated with increased risks of gestational diabetes, preterm delivery and cesarean section.

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