What is the broad area in which the Nobel Prize winners for the year 2006 in Physiology or Medicine, worked to get the Prize?

The 2006 Nobel Prize in Physiology or Medicine was awarded to Andrew Fire and Craig Mello for the discovery of RNA interference (RNAi), a mechanism in which double-stranded RNA triggers sequence-specific silencing of genes by degrading the corresponding mRNA, thereby regulating gene expression. This discovery revealed a new fundamental mechanism for the control and flow of genetic information from DNA to functional products, profoundly affecting how cells regulate gene activity and information transfer within cells [2]. Thus the broad area of their work is best described as relating to the flow and regulation of genetic information.

Sources

1. [1] https://www.nobelprize.org/uploads/2018/06/popular-medicineprize2006.pdf
2. [2] https://www.nobelprize.org/prizes/medicine/2006/advanced-information/