Rare Diseases : Multi-Gene Testing is a Necessity For Diagnosis Of Rare’ Diseases

12_infertility-2-minRare Disease : A disease is considered to be ‘rare’ when it affects one in about 2,000 individuals in the population. There are anywhere between 5,000 to 8,000 diseases that are considered to be ‘rare diseases’ according to WHO statistics. Although individually rare, collectively, the incidence of rare diseases could be as high as 6-8% in certain populations. In developing countries like India, owing to the social structure, high birth rate and high degree of consanguinity, about half a million children are born every year with rare disorders.

Nearly 80% of rare diseases are considered to be genetic diseases, where due to mutation in a gene, the normal function of the protein (encoded by the gene) is lost or the protein acquires abnormal function (gain-of-function), which results in a disease.  A multi-centric study on Indian population showed that the frequency of newborns with malformations, such as neural tube defects and musculoskeletal disorders were upto 2%, while other genetic conditions such as beta-thalassemia, metabolic disorders were as high as one in 2,500. One of the major reasons for referral to genetic centers is seen to be for reproductive genetics, comprising prenatal diagnosis, recurrent abortions, infertility, and even multiple congenital anomalies. disease is considered to be ‘rare’ when it affects one in about 2,000 individuals in the population. There are anywhere between 5,000 to 8,000 diseases that are considered to be ‘rare diseases’ according to WHO statistics. Although individually rare, collectively, the incidence of rare diseases could be as high as 6-8% in certain populations. In developing countries like India, owing to the social structure, high birth rate and high degree of consanguinity, about half a million children are born every year with rare disorders.

Ultrasonography : Role of Ultrasonography in Pregnancy

Conventional genetic testing for rare diseases focus mostly on testing or sequencing of single gene(s), followed by a deletion/duplica¬tion analysis by multiplex ligation-dependent probe amplifi¬cation (MLPA). This sequential testing strategy performed in a reflex-testing mode is time consuming and expensive, and thus not ideal for a developing country like India. New advances in genomic technologies, such as multi-gene panels, based onNGS (next-generation sequencing) allows us to detect all types of mutations, including large deletions/duplications, thus allowing us to perform a comprehensive genetic testing in a cost-effective manner.

Go to page 2 to read more  : Multi-gene testing vs single gene testing

Prev1 of 3
Use your ← → (arrow) keys to browse

Leave a Reply

Your email address will not be published. Required fields are marked *