Dictionary > Triple-X syndrome

Triple-X syndrome

Definition
noun
A genetic condition in which a female has an extra X chromosome
Supplement
In humans, the sex chromosomes are the X chromosome and the Y chromosome. The basis of sex determination in humans is on the pair of sex chromosomes present in an individual. For instance, females have a pair of two X chromosomes whereas males have one X chromosome and one Y chromosome. There are instances though when certain individuals have a different set of sex chromosomes. An example is the so-called triple X syndrome, which is characterized by having an extra X chromosome.
Triple-X syndrome is a genetic condition in certain females wherein there is an extra X chromosome in each of the cell. Microscopic observation of the cell reveals twin Barr bodies rather than the normal XX complement. Karyotyping results in a total of 47 chromosomes due to the presence of an additional X chromosome apart from the other two X chromosomes. Thus, it is also called trisomy X. There are instances though wherein only some of the cells have an extra X chromosome; they are referred to as 46,XX/47,XXX mosaics.
The common physical features of females with triple-X syndrome are having a tall stature, epicanthic folds, and poor muscle tone. Other symptoms include learning disabilities, speech and behavioral problems, seizures, and kidney problems.
Also called:

  • 47,XXX syndrome
  • triplo-X syndrome
  • trisomy X
  • XXX syndrome

See also:

  • sex chromosome
  • X chromosome
  • Y chromosome


  • You will also like...

    Hominid
    The Hominids

    The hominid family diversified from the apes around 6 to 8 million years ago. Since then, the evolutionary path has prov..

    Human Reproduction
    Human Reproduction

    Humans are capable of only one mode of reproduction, i.e. sexual reproduction. Haploid sex cells (gametes) are produced ..

    Electromagnetic spectrum of a brain
    Sleep and Dreams – Neurology

    While learning and intelligence are associated with the functions of a conscious mind, sleep and dreams are activities o..

    Neural Control Mechanisms
    Neural Control Mechanisms

    Neurons generate electric signals that they pass along to the other neurons or target tissues. In this tutorial, you wil..

    Disturbance on a still water
    Abiotic Factors – Water Conditions

    A still body of water may be disturbed by a variety of factors. One of them is wind. In fact, it is considered as the pr..

    Schematic diagram of DNA replication
    DNA Structure & DNA Replication

    DNA is a double helix structure comprised of nucleotides. A nucleotide, in turn, is made up of phosphate molecule, deoxy..

    Related Articles...

    No related articles found

    See all Related Topics