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(cell and molecular biology)
The presence in triplicate of one of the chromosomes of the complement.



the presence of one or a few nonhomologous extra chromosomes in the chromosome set of a diploid organism. Organisms (or cells) in which one, two, or more chromosomes present themselves as three homologues are called simple trisomics, double trisomics, and so forth. Trisomy is caused by the failure of chromosomes to separate (nondisjunction) during cell division. Some specific severe disorders are the result of trisomy occurring in specific chromosomes.

References in periodicals archive ?
She is the author of the book, "Living with Klinefelter Syndrome, Trisomy X and 47, XYY: www.
The discordant fetal sex classification sample was classified as unreportable based on discordant " score and risk-score trisomy classification results (Fig.
The value of NIPT in this select population was that it was possible to avoid a number of invasive tests in the small group with a high adjusted risk for trisomy 21.
5-year-old male case of mosaic trisomy 9 with a moderate developmental delay.
When prenatal or neonatal diagnosis of trisomy 18 is made, the counselling of the family should be realistic but not desolate.
The chromosomal analysis were undertaken in 22 cases, out of which 20 (91%) cases had free trisomy 21, 1 case had trisomy 21 with translocation (46, XY, der (21;21)(q10;q10),+21), and 1 case had mosaic trisomy 21 (47, XY,+21/46, XY) [Table 2].
You explain to your patient that the chance her fetus has trisomy 13 is far lower than 99%, based in part on the very low prior risk given her age.
The primary outcome was the area under the receiver-operating-characteristic (ROC) curve for trisomy 21.
In a study of about 1,900 low-risk women whose mean maternal age was 30 years, cfDNA testing detected all cases of trisomy 21.
3-5] A case report follows of a patient diagnosed with Trisomy 13, with multiple congenital anomalies including bilateral SHM.
Down Syndrome Research's mission is to find ways to improve the lives of people born with trisomy 21, the cause of Down syndrome.