Genetic disorders are not that rare

Everything is characterised by a name. A name or a title offers a direct insight into things. “Rare” is a misnomer applied to a class of diseases driving one away from it, and more towards an event or a disease or a challenge that may be perceived as common. The World Rare Diseases Day is observed on February 28.

When a child inherits a disorder, it may prove deadly for the child for fault of his own or his uninformed parents. At the time of conception, the genetic combinations were skewed, and hence, it was a gamble with luck. These happenings will continue until such time the couples, before making a decision to bear a child, undergo a complete genome analysis and computation thereof using the best algorithms available to rule out any predictable and preventable “rare” or “life-style” disease in their child.

Will the society reach the point where it will replace matching religion, caste, astrology, or even “life-styles” with “genome matching”? Or, will a couple, deeply in love, discuss their genetic make-ups before tying the knot?

Even though privacy laws are looming large, will some dating and matrimonial sites give an indication of the prospective bride or groom’s genetic attributes?

This may be a long way away destined for a new world. In the present day, however, these measures must not hinder love. Falling in love must be natural without any prejudices. But society must be prepared, too.

But, since both our public and private health sectors are ailing with their own maladies, giving support to people with life-style disorders seems like a distant dream.

This is a common phenomenon in developing and developed economies to find prophylactic measures, therapeutic cures, and innovations required for health management, missing.

It is time to realise that down the heredity line, children of our grandchildren may face problems that are much more complex than those today. Genetic disorders may become widespread in the future.

It is not the percentage, normally used to classify a genetic disorder as “rare” that counts, but the absolute numbers and its inevitable increase in line with the teeming population.

That said, it is more reasonable to call these disorders “common genetic disorders” as the word “common” for lack of a better name, may in all sincerity, alert the policy makers and funding organisations to pay more attention.

It is frequently mentioned that there are over 7,000 distinct types of genetic disorders referred to as “rare diseases” in the world’s human population, with some being more prevalent than the others.

This number in all likelihood will increase as technology, information and knowledge for diagnosis and prediction get better. As a population creates its progeny, new genetic combinations can surface, which were hitherto unidentified genetic disorders.

The pairing and genetic recombination of alleles (each of two or more alternative forms of a gene that arise by mutation and are found at the same place on a chromosome) continue to result in new genetic attributes, irrespective of consanguinity or marriage between people belonging to distant genetic pools.

The resultant genotype may manifest into desirable or undesirable phenotype (the composite of an organism’s observable characteristics or traits), or it may or may not carry over the biochemical and physiological traits.

Human genome project

The human genome project has revealed the presence of 24,000 genes spread across 23 pairs of chromosomes with about 19,000 to 20,000 protein coding genes. The balance has been marked as regulatory DNA sequences coding for genetic transcription factors and many other types of DNA required for the stable sustenance of the human genome and hereditary bequest.

Theoretically, there is every chance of mutated chromosomes of a gene or genes crossing over during parental chromosome recombination, manifesting into ill consequences in the new born children. This may develop into a problem as the child grows.

Moreover, there is also the effect of the environment on genes (epigenetics) which causes modification of gene-encoded proteins, which in turn, influences their performance. With around 350 million people affected in the world, genetic disorders are a common phenomenon.

The actual numbers might be more than what is being reported. We must, therefore, have in place appropriate predictive, preventive and curative measures fast-tracked by public and private enterprises to promote a healthy society. This will lessen the burden on the patient’s family, too.

In conclusion, “rare genetic disorders” are actually not that “rare,” they are quite common.

(The writer, a molecular geneticist, is currently working as a Principal Consultant, Department of IT-BT and S&T, Government of Karnataka)