Rare diseases — despite the infrequency that the name confers — cumulatively affect around 350 million people worldwide. This figure includes roughly seventy million Indians. Could genome sequencing prove to be the tool that begins to spark medical innovation and diagnosis for the millions affected by such disorders?
The Economic Times notes a recent case in which genome sequencing has proven to be an effective means of diagnosis for conditions classified as rare diseases. A woman, who was at the time three months pregnant, came to see a paediatrician at Government Medical College in Kozhikode wanting to know if there was a way to find out if her unborn child could develop a rare immune disease her firstborn was suffering from.
The article notes that the white blood cells in her six year-old daughter’s body behaved abnormally, leading to organ infections and rimpaired growth. Doctors, so far, had been unable to cure the girl, she said. While the name of the condition is never revealed in the article, many rare diseases also fall under the categorisation of autoimmune disorders, such as Asherson’s syndrome.
The woman underwent an antenatal procedure to retrieve genetic material from the unborn child. This was analysed and compared to genetic testing performed on the six-year-old daughter. The tests brought the welcome news that the woman’s baby would not have the same genetic disorder as her previous child.
This test had the luxury of comparing directly to a relative. However, most testing has to be compared to databases with one major drawback. “No reliable genetic information of Indians is available and for research, our scientists have to rely on gene data banks from the US and the UK — or of Caucasians,” said Council of Scientific and Industrial Research (CSIR) director-general Shekhar C. Mande.
As of now, Indian genomes only represent 0.2 percent of the global genetic databanks. The current majority of genomes — around 96 percent — are of European ancestry. Ignoring the study of Indian genes leaves what could be a medical goldmine all but untapped.
Previous genomic studies conducted in India have uncovered genes exclusive to the Indian population that present a unique risk in developing diabetes. Knowledge of risks such as these can allow for the Indian medical system, as well as government policy, to be better informed when making decisions regarding disease prevention and treatment.