A mutant protein is the protein product encoded by a gene with mutation. Mutated protein can have single amino acid change (minor, but still in many cases significant change leading to disease) or wide-range amino acid changes by e.g. truncation of C-terminus after introducing premature stop codon.
See also Site-directed mutagenesis Phi value analysis missense mutation nonsense mutation point mutation frameshift mutation silent mutation single-nucleotide polymorphism
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