Scientists Discover Key Patterns In The Packaging Of Genes

Although every cell of our bodies contains the same genetic instructions, specific genes typically act only in specific cells at particular times. Other genes are "silenced" in a variety of ways. One mode of gene silencing depends upon the way DNA, the genetic material, is packed in the nucleus of cells.

When packed very tightly around complexes of proteins called histones, the DNA double helix is rendered physically inaccessible to molecules that mediate gene expression.

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