Noun
trisomy (countable and uncountable, plural trisomies)
(cytology) The presence of three copies, instead of the normal two, of a particular chromosome of an organism.
About a week and a few tests later, they got the diagnosis: Trisomy 13, a rare genetic disorder involving multiple life-threatening abnormalities that is frequently described in medical literature as “incompatible with life.” Source: Internet
Besides Down syndrome (trisomy 21), some other human trisomies are extra Y or X chromosomes, and Edwards syndrome (trisomy 18) and Patau syndrome (trisomy 13), both of which have extremely high newborn fatality rates. Source: Internet
Like Down syndrome, trisomy 18 and trisomy 13 are more common as maternal age increases. Source: Internet
“McCall has Trisomy 21, which means she has a third copy of chromosomes in the 21st chromosome set,” said Hestwood. Source: Internet
The most common error in chromosome replication is trisomy 21, where the new cell gets three copies of chromosome 21, instead of two. Source: Internet
Trisomy 18 is a genetic disorder that is caused by the existance of two extra 18th chromosomes, which can interfere with the development of the baby. Source: Internet