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Each child of a parent with HD, either male or female, has a 50% chance of inheriting the gene mutation that eventually leads to HD.
HD occurs in all parts of the world.
Genes are made up of nucleotides represented by the letters CAGT. The higher the number of CAG repeats, the greater the risk of HD. Repeats of 40 or more eventually lead to Huntington disease.
Genetic testing for HD is done on a sample of blood in a specialized laboratory to determine the number of CAG repeats in both copies of an individual’s HD gene.

Each child of a parent with HD, either male or female, has a 50% chance of inheriting the gene mutation that eventually leads to HD.
HD occurs in all parts of the world.
Genes are made up of nucleotides represented by the letters CAGT. The higher the number of CAG repeats, the greater the risk of HD. Repeats of 40 or more eventually lead to Huntington disease.
Genetic testing for HD is done on a sample of blood in a specialized laboratory to determine the number of CAG repeats in both copies of an individual’s HD gene.