Sequence specificity in CpG mutation hotspots.

J Ollila; I Lappalainen; M Vihinen

doi:10.1016/0014-5793(96)01075-7

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PubMed · 8914970

Sequence specificity in CpG mutation hotspots.

J Ollila·I Lappalainen·M Vihinen

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Abstract

CpG dinucleotides are efficiently methylated in vertebrate genomes except in the CpG islands having a high C+G content. Methylated CpGs are the single most mutated dinucleotide. Sequences surrounding disease causing CpG mutation sites were analyzed from locus-specific mutation databases. Both tetra- and heptanucleotide analyses indicated clear overall sequence preference for having pyrimidines 5' and purines 3' to the mutated 5-methylcytosine. The most mutated tetranucleotides are TCGA and TCGG, the former being also a frequent restriction and modification site. The results will help in elucidating the still controversial mutation mechanism of CpG doublets.

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Agammaglobulinaemia Tyrosine Kinase Agammaglobulinemia Base Sequence DNA Methylation Dinucleoside Phosphates Factor VIII Genes, p53 Genetic Linkage Hemophilia A Molecular Sequence Data Mutation Oligodeoxyribonucleotides Phenylalanine Hydroxylase Phenylketonurias Point Mutation Protein-Tyrosine Kinases X Chromosome Journal Article Research Support, Non-U.S. Gov't

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J Ollila, I Lappalainen, M Vihinen. 1996-11-04. Sequence specificity in CpG mutation hotspots.. https://doi.org/10.1016/0014-5793(96)01075-7

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