A point [[mutation]] is the most limited type of mutation, whereby a single base [[nucleotide]] is replaced with another nucleotide. Sometimes the expression "point mutation" can also include the addition or subtraction of a single base pair.
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A '''point mutation''' is the most limited type of [[mutation]], whereby a single base [[nucleotide]] is replaced with another nucleotide. Sometimes the expression "point mutation" can also include the addition or subtraction of a single base pair.
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The sickle-cell disease is caused by a single point mutation in the beta hemoglobin gene, whereby a GAG codon is converted into GTG. The GTG then mistakenly encodes the amino acid valine instead of glutamic acid.
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The sickle-cell disease is caused by a single point mutation in the beta [[hemoglobin]] gene, whereby a GAG codon is converted into GTG. The GTG then mistakenly encodes the [[amino acid]] valine instead of glutamic acid.