The field of molecular biology has a profound impact in medical science investigation. Major advances in molecular biology over the last four decades have stimulated research and progress in almost all the disciplines of life science. 

This driving force involves:

 (1) the development of more and more sophisticated experimental techniques in molecular biology with a broad, interdisciplinary applicability; 

(2) the ever-expanding flow of information of technical novelties and scientific discoveries across the scientific community; and 

(3) the development of specific software and continuously updated databases for, respectively, analyzing and storing data on genotypes, gene expression levels, cytogenetic profiles and other molecular features.

 This has changed the rationale and approach of scientific experimentations allowing revolutionizing discoveries not only in molecular biology but also in biochemistry, biophysics, biotechnology, cell biology, and genetics. One major example is the innovation in high-throughput biology, next generation sequencing and recombinant DNA technology, which made possible to unveil the high complexity of the genome and elucidate the precise mechanisms for the transmission of the genetic information. So, it is now proven that gene expression, DNA replication, DNA repair, and sister chromatid segregation are processes much more complicated than previously thought. 

This complexity includes, but is not limited to:

 (1) the existence of interconnected regulatory pathways involving also previously unexpected actors, such as non-coding RNAs;

 (2) the relevance of epigenetic mechanisms and post-transcriptional modifications;

 (3) the importance of the correct execution, timing, sequentiality and coordination of all cell cycle events; 

(4) the pleiotropic functions of players operating in these processes; and 

(5) the influence of the energetic metabolisms and environmental signals. Moreover, it has become evident that the deregulation of these molecular processes is associated with, and in certain circumstances is the direct cause of, a wide range of pathological conditions. Although this module is focused on life sciences, it is, however, necessary to mention the biomedical relevance of molecular biology-related investigations for drug discovery and the development of a more personalized medicine.

Given the rapidly changing and continuously evolving nature of the molecular biology field, we can anticipate that the revolutionary impact of molecular biology in medical sciences is only at the beginning and is far from being finished.