India is home to a heterogenous population and owing to the prevalence of multiple endogamous groups, the incidence of rare diseases is on the rise. According to WHO, rare disease is referred to as a health disorder with prevalence of 1 or less in 1000.
Though individual rare diseases have a low prevalence, collectively they affect nearly 6-8% of the population in any country. About 80% of rare diseases are genetic in origin and thus are present throughout a person’s life, even if symptoms do not immediately appear. India has an estimated 72 to 96 million people affected by rare diseases, which is a significant number.
CLASSIFICATION OF RARE DISEASES
• Chromosomal – It affects the structures that hold our genes/DNA within each cell. Eg. Turner Syndrome, Trisomy 13.
• Single gene (Monogenic) – It occurs due to changes in a single gene. Eg. Thalassemia, spinal muscular atrophy..
• Complex (Multifactorial) – These arise from combination of gene mutations and/or environmental factors. Eg. Certain hereditary cancers, congenital heart conditions.
RARE DISEASES IN INDIA
Around 450 rare diseases are currently recorded in the country that includeHaemophilia, Thalassemia, Sickle-cell Anaemia and Primary Immuno Deficiency in children, auto-immune diseases, Lysosomal storage disorders such as Pompe disease, Hirschsprung disease, Gaucher’s disease, Cystic Fibrosis, Hemangiomas and certain forms of muscular dystrophies. The list is however expanding owing to newer discoveries made due to the science of genomics.
EARLY DIAGNOSIS AND AWARENESS IS THE KEY
Out of the 80% of genetic rare disease, 50% of these affect children and 35% of deaths in patients with rare diseases occur in infants younger than one year old. A rare disease typically takes 8 visits to a medical professional before it is correctly diagnosed. Most of the diseases require lifelong management which could significantly add to the economic burden of both the affected families and the nation.
Rare diseases are preventable through early diagnosis and awareness about the diseases and their inheritance. A well-informed medical professional with the help of experienced genetic counselors can help families with history of rare disease in prevention and management. Carrier screening for genetic mutations in parents can help them make informed decisions about future pregnancies in case of prior history of a rare disease. Molecular diagnostic tests such as non-invasive prenatal testing (NIPT) based on history of birth defects in previous pregnancies or abnormal findings in screening tests such as ultrasound, are helpful in identifying presence of genetic abnormalities in developing fetuses.
FUTURE OF RARE DISEASES IN INDIA
Owing to the expense of the treatment procedure, the government of India has set up high level committees for the formulation of the ‘Policy on treatment of rare diseases’. The policies highlight several short- and long-term measures that deal comprehensively with the same. It helps to strike a balance between the access and the treatment with sustainable medical facilities.
Indian Government has also proposed to fund a one-time treatment cost of Rs. 15 lakhs for the treatable rare diseases under the flagship health insurance scheme named Ayushman Bharat’s Pradhan Mantri Jan Arogya Yojana. This is a landmark step in providing solution to those who are unable to meet the heavy expenditure of the treatment and remain untreated throughout.
Rare diseases contribute to a significant disease burden in India and with the help of Genomics-based solutions, we can enable accelerated diagnosis, prevention and management of these diseases.
The writer is CEO, MedGenome Labs.