DNA methylation variations between mono - and dizygotic twins

Monozygotic twins (MZ) who have a common genotype may show phenotypic discordance. One of the possible explanations is the existence of epigenetic changes which occur as DNA methylation alterations. DNA methylation changes were studied in 16 MZ twin pairs and 8 dizygotic (DZ) twin pairs using CRED-RA technique. The most suitable primer (5'-GATGACCGCC-3') was selected out of 20, random, decamer primers. Significant DNA methylation changes were observed in either MZ or DZ twins. Each MZ twin pair share common RAPD profile, however some of them have their own methylation profile regardless their backgrounds. Environmental conditions alone should not be accounted for phenotypic discordance between MZ twins, although external factors may influence genetic and epigenetic nature and also the phenotype. Our results might be also useful for the identification of MZ twins. To our knowledge, tins is the first study to use CRED-RA in human genetics