Nonsense Mutations- the term "nonsense mutation is used because the stop codon has "no sense" for an amino acid. Nonsense mutations cause the protein to be cut off early and therefore incomplete, which usually renders it non-functional. Cystic fibrosis is a disease caused by a nonsense mutation.
Deletion Mutation- In genetics, a deletion (also called gene deletion, deficiency, or deletion mutation) (sign: Δ) is a mutation (a genetic aberration) in which a part of a chromosome or a sequence of DNA is missing. Deletion is the loss of genetic material. Any number of nucleotides can be deleted, from a single base to an entire piece of chromosome.[1] Deletions can be caused by errors in chromosomal crossover duringmeiosis. This causes several serious genetic diseases. Deletion also causes frameshift.
Insertion Mutation-In genetics, an insertion (also called an insertion mutation) is the addition of one or more nucleotide base pairs into a DNAsequence. This can often happen in microsatellite regions due to the DNA polymerase slipping. Insertions can be anywhere in size from one base pair incorrectly inserted into a DNA sequence to a section of one chromosome inserted into another.
On a chromosome level, an insertion refers to the insertion of a larger sequence into a chromosome. This can happen due to unequal crossover during meiosis.
Point mutation-A point mutation, or single base substitution, is a type of mutation that causes the replacement of a single base nucleotidewith another nucleotide of the genetic material, DNA or RNA.
Translocation Mutation-n genetics , a chromosome translocation is a chromosome abnormally caused by rearrangement of parts between non humologous chromosomes a genes fusion .may be created when the translocation join two otherwise separate genes , the occurrence of which is common in cancer .
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