HEREDITY
MUTATIONS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Additions
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Deletions
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Both additions and deletions
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Point mutations
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Detailed explanation-1: -A frameshift variant occurs when there is an addition or loss of nucleotides that shifts the grouping and changes the code for all downstream amino acids. The resulting protein is usually nonfunctional. Insertions, deletions, and duplications can all be frameshift variants.
Detailed explanation-2: -Frameshift mutations occur when the coding region of a gene is altered by addition or deletion of a number of base pairs that is not a multiple of three. The occurrence of a deletion versus an insertion type of frameshift depends on the nature of the transient intermediate structure formed during DNA synthesis.
Detailed explanation-3: -A frameshift mutation is produced either by insertion or deletion of one or more new bases. Because the reading frame begins at the start site, any mRNA produced from a mutated DNA sequence will be read out of frame after the point of the insertion or deletion, yielding a nonsense protein.
Detailed explanation-4: -Frameshift. Since protein-coding DNA is divided into codons three bases long, insertions and deletions can alter a gene so that its message is no longer correctly parsed. These changes are called frameshifts.