DNA methylation typically occurs at ________ dinucleotide sites and generally represses gene expression.
- AT
- GC
- CG
- TA
Answer: CG
CpG islands (CG dinucleotides) are common methylation sites. Methyl groups added to cytosine by DNMT enzymes silence genes. Epigenetic changes influence development, disease, and inheritance. [[NCERT Biology Class 12]]