Exploring the common molecular basis for the universal DNA mutation bias: Revival of Löwdin mutation model

• Published in: Biochemical and biophysical research communications 2011-06, Vol.409 (3), p.367-371
• Main Authors: Fu, Liang-Yu, Wang, Guang-Zhong, Ma, Bin-Guang, Zhang, Hong-Yu
• Format: Article
• Language: English
• Subjects: Animals; CpG hypermutation; DNA - chemistry; DNA - genetics; Löwdin model; Models, Genetic; Mutation; Oxidative damage; Protons; UV-radiation damage
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1016/j.bbrc.2011.05.017

► There exists a universal G:C→A:T mutation bias in three domains of life. ► This universal mutation bias has not been sufficiently explained. ► A DNA mutation model proposed by Löwdin 40years ago offers a common explanation. Recently, numerous genome analyses revealed the existence of a universal G:C→A:T mutation bias in bacteria, fungi, plants and animals. To explore the molecular basis for this mutation bias, we examined the three well-known DNA mutation models, i.e., oxidative damage model, UV-radiation damage model and CpG hypermutation model. It was revealed that these models cannot provide a sufficient explanation to the universal mutation bias. Therefore, we resorted to a DNA mutation model proposed by Löwdin 40years ago, which was based on inter-base double proton transfers (DPT). Since DPT is a fundamental and spontaneous chemical process and occurs much more frequently within GC pairs than AT pairs, Löwdin model offers a common explanation for the observed universal mutation bias and thus has broad biological implications.