Occasionally, the patient with features of Turner’s syndrome is found to be X-chromatin positive. This abnormal X-chromatin negative finding in the majority of Turner’s syndrome females is similar to the result found in a normal male, who also has only one X chromosome, and differs from the X-chromatin positive condition observed in the normal female, who has two X chromosomes. The typical Turner’s syndrome patient, who has 45 chromosomes and only one sex chromosome (an X), has no Barr bodies and is, therefore, X-chromatin negative. Cells from the lining of the mouth are stained for the presence or absence of X-chromatin or Barr bodies, which represent a portion of an inactivated X chromosome. (ii) X-ChIP: Proteins are cross-linked to the DNA. N-ChIP is restricted to proteins that are very tightly associated with chromatin, typically limiting this type of ChIP to histones and their modifications (OTNeill and Turner, 2003). Cienfuegos According to this paper most individuals with Turner Syndrome are chromatin negative: "One of the initial laboratory procedures used to confirm or rule out this diagnosis involves a sex chromatin determination from a buccal smear. of the chromatin is achieved by micrococcal nuclease digestion, resulting in a nucleosome based resolution.
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