Lecture 3 Cancer Genomics
Studentnummer = 2711368
Oncogenes can be activated by a mutation, an amplification or a translocation. Usually there is
retention of heterozygosity.
There are several types of mutations:
▪ Substitutions
o transitions (C<>T, A<>G)
o transversions (C/T<>A/G, A/G<>C/T)
▪ Insertions, Deletions, “InDels”: out of frame
A & G are purines, C & T are pyrimidines. Between purine-purine / pyrimidine-pyrimidine =
transition. Transversion is between purine & pyrimidine.
Effect: synonomous/nonsynonomous, missense, nonsense, frame shift, splice site, loss of function,
gain of function, dominant-negative. Synonymous mutations → the DNA sequence still codes for the
same amino acid. Non-synonomous is another protein (missense). Nonsense/truncating mutation =
STOP codon (UGA, UAA, UAG). At the beginning of a new exon: TAG C. Dominant negative mutation
can occur when a mutant protein is overexpressed or when a protein acts in complexes.
Studentnummer = 2711368
Oncogenes can be activated by a mutation, an amplification or a translocation. Usually there is
retention of heterozygosity.
There are several types of mutations:
▪ Substitutions
o transitions (C<>T, A<>G)
o transversions (C/T<>A/G, A/G<>C/T)
▪ Insertions, Deletions, “InDels”: out of frame
A & G are purines, C & T are pyrimidines. Between purine-purine / pyrimidine-pyrimidine =
transition. Transversion is between purine & pyrimidine.
Effect: synonomous/nonsynonomous, missense, nonsense, frame shift, splice site, loss of function,
gain of function, dominant-negative. Synonymous mutations → the DNA sequence still codes for the
same amino acid. Non-synonomous is another protein (missense). Nonsense/truncating mutation =
STOP codon (UGA, UAA, UAG). At the beginning of a new exon: TAG C. Dominant negative mutation
can occur when a mutant protein is overexpressed or when a protein acts in complexes.
