Trisomy 23 is 23 pairs of chromosomes or extra chromosomes.
Trisomy is the presence of an extra chromosome.
This can arise as a result of non-disjunction, when homologous chromosomes fail to separate at meiosis resulting in a germ cell containing 24 chromosomes rather than 23.
Trisomy of any chromosome can occur, but all except trisomies 21, 18, 13, X and Y are lethal in utero.
7q11.23 duplication syndrome is characterized by delayed motor, speech, and social skills in early childhood; neurologic abnormalities (hypotonia, adventitious movements, and abnormal gait and station); speech sound disorders including motor speech disorders (childhood apraxia of speech and/or dysarthria).
Humans have 23 pairs of chromosomes.
A trisomy is a chromosomal condition characterised by an additional chromosome.
A person with a trisomy has 47 chromosomes instead of 46.
Down syndrome, Edward syndrome and Patau syndrome are the most common forms of trisomy.
Klinefelter syndrome is caused by an additional X chromosome.
This chromosome carries extra copies of genes, which interfere with the development of the testicles and mean they produce less testosterone (male sex hormone) than usual.
The term trisomy describes the presence of three chromosomes instead of the usual pair of chromosomes.
For example, trisomy 21, or Down syndrome, occurs when a baby has three #21 chromosomes.
Other examples are trisomy 18 and trisomy 13, fatal genetic birth disorders.