Scientists have identified 42 new regions in the human genome associated with rheumatoid arthritis, paving way for new drugs to treat the autoimmune disease.
The discovery brings the total number of known rheumatoid arthritis genome to 101, researchers said.
Researchers performed a genome-wide association study meta-analysis on over 100,000 subjects of European and Asian descent - 29,880 rheumatoid arthritis patients and 73,758 controls - by analysing around 10 million genetic variants called single nucleotide polymorphism (SNPs).
By conducting bio-informatics studies integrating existing datasets with this new information, the researchers were able to pinpoint 98 genes in these 101 loci that could potentially contribute to the onset of rheumatoid arthritis.
By integrating their findings with existing drug databases they demonstrate that these genes indeed possess many overlapping regions with the genes targeted by approved rheumatoid arthritis drugs - although this was not known when the drugs were developed.
The team identify existing drugs used to treat cancer that also target rheumatoid arthritis genes and could potentially be used as therapy for the disease, such as CDK4/6 inhibitors.
The study also reveals that there is significant overlap between the genes involved in rheumatoid arthritis, human primary immunodeficiency disorders and blood cancers.
"This study sheds light on the fundamental genes, pathways and cell types that contribute to the onset of rheumatoid arthritis and provides evidence that the genetics of rheumatoid arthritis can provide important information for drug discovery," researchers said.
"While there are previous anecdotal examples, our study provides a systematic approach by which human genetic data can be efficiently integrated with other biological information to derive biological insights and drug discovery," they added.
The largest international study to date into the genetic basis of rheumatoid arthritis was conducted by Dr Robert M Plenge from the Harvard Medical School and Dr Yukinori Okada from the RIKEN Center for Integrative Medical Sciences in Japan, collaborating with colleagues from 70 institutions worldwide.
The study was published in the journal Nature.
