Scientists have found that genetic variation increases the risk of leprosy in Indian population.

Even though leprosy control has improved significantly due to effective multi-drug therapy, India ranks first in terms of both prevalence and new cases, which is about 58 per cent of global diseases burden. The contribution remained consistent over the years with increased detection among children in recent years. In the study published in Plos One journal, researchers from India and Germany have investigated the possible contribution of genetic variations in genes which are vital for immunological control of bacterial pathogen. A case control study design was employed with Indian leprosy patients either with few or more bacteria forms of leprosy along with infection-free individuals from the same ethnic population.

Scientists from the Institute of Tropical Medicine, University of Tubingen, Germany, LEPRA- Blue Peter Public Health and Research Centre, Hyderabad, CSIR- Centre for Cellular and Molecular Biology and School of Life Sciences, Bharathiar University, Coimbatore carried out the study, according to a CCMB press release here.

The researchers found that mutations in three immune recognition genes—NOD2 (nucleotide oligomerization domain 2) RIPK2 (Receptor-interacting serine-threonine kinase 2) and LRRK2 (leucine rich reporter kinase 2) increase the risk of leprosy among Indians.

Dr. Thirumalaisamy Velavan, lead author of the study and German scientist of Indian origin at the Institute of Tropical Medicine, University of Tubingen said: “The results increases our understanding on complex molecular and cellular mechanisms that are regulated by the pathogen Mycobacterium leprae during its clinical course and points to additional genetic factors that may explain the extraordinary predominance of leprosy in the Indian sub-continent.”

Another author of the paper, Dr. Vijayalakshmi Valluri, acting director of LEPRA-BPHRC, India said leprosy prevalence was high in certain districts of AP, as evident from the number of new cases enrolled in 2012 in their centre. She said the actual incidence among household contacts and the relative risk for them varied considerably due to their genetic composition.

India ranks first in terms of both prevalence and new cases, which is about 58 per cent of global diseases burden