When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Barr body - Wikipedia

    en.wikipedia.org/wiki/Barr_body

    Barr bodies can be seen in neutrophils at the rim of the nucleus. In humans with more than one X chromosome, the number of Barr bodies visible at interphase is always one fewer than the total number of X chromosomes. For example, people with Klinefelter syndrome (47, XXY) have a single Barr body, and people with a 47, XXX karyotype have two ...

  3. X-inactivation - Wikipedia

    en.wikipedia.org/wiki/X-inactivation

    The Xist gene is expressed at high levels on the Xi and is not expressed on the Xa. [39] Many other genes escape inactivation; some are expressed equally from the Xa and Xi, and others, while expressed from both chromosomes, are still predominantly expressed from the Xa. [40] [41] [42] Up to one quarter of genes on the human Xi are capable of ...

  4. Sex-chromosome dosage compensation - Wikipedia

    en.wikipedia.org/wiki/Sex-chromosome_dosage...

    Replicating the actual gene is impossible; thus organisms instead equalize the expression from each gene. For example, in humans, female (XX) cells randomly silence the transcription of one X chromosome, and transcribe all information from the other, expressed X chromosome. Thus, human females have the same number of expressed X-linked genes ...

  5. Klinefelter syndrome - Wikipedia

    en.wikipedia.org/wiki/Klinefelter_syndrome

    In the past, the observation of the Barr body was common practice, as well. [47] To investigate the presence of a possible mosaicism, analysis of the karyotype using cells from the oral mucosa is performed. Physical characteristics of a Klinefelter syndrome can be tall stature, low body hair, and occasionally an enlargement of the breast.

  6. XXYY syndrome - Wikipedia

    en.wikipedia.org/wiki/XXYY_syndrome

    48,XXYY syndrome is a condition related to the X and Y chromosomes (the sex chromosomes). People normally have 46 chromosomes in each cell.Two of the 46 chromosomes, known as X and Y, are called sex chromosomes because they help determine whether a person will develop male or female sex characteristics.

  7. X-chromosome reactivation - Wikipedia

    en.wikipedia.org/wiki/X-chromosome_reactivation

    X chromosome reactivation (XCR) is the process by which the inactive X chromosome (the Xi) is re-activated in the cells of eutherian female mammals. Therian female mammalian cells have two X chromosomes, while males have only one, requiring X-chromosome inactivation (XCI) for sex-chromosome dosage compensation.

  8. Turner syndrome - Wikipedia

    en.wikipedia.org/wiki/Turner_syndrome

    Turner syndrome (TS), commonly known as 45,X, or 45,X0, [note 1] is a chromosomal disorder in which female cells have only one X chromosome instead of two, or are partially missing an X chromosome (sex chromosome monosomy) leading to the complete or partial deletion of the pseudoautosomal regions (PAR1, PAR2) in the affected X chromosome.

  9. Nuclear sexing - Wikipedia

    en.wikipedia.org/wiki/Nuclear_sexing

    Nuclear sexing is a technique for genetic sex determination in those species where XX chromosome pair is present. Nuclear sexing can be done by identifying Barr body, a drumstick like appendage located in the rim of the nucleus in somatic cells. Barr body is the inactive X chromosome which lies condensed in the nucleus of somatic cells. A ...