Non-B DNA structures can have important biological roles, but they can also cause problems, such as genomic instability and disease.
A-DNA is believed to play a role in certain biological processes, such as DNA replication and gene expression.
[3] It is stabilized by the alternating purine-pyrimidine sequence and can form in regions of DNA with high GC-content, supercoiling, or negative superhelicity.
[4] H-DNA is stabilized by Hoogsteen base pairing and can cause mutations, rearrangements, and genome instability.
H-DNA is thought to be involved in DNA replication, recombination, and repair, but its precise biological functions remain unclear.