An overview of rare genetic disorders and recent diagnostic approaches

Abstract

Genetic disorders are the leading causes of mortality and morbidity in humans. The prevalence of genetic diseases varies widely between different clusters depending on their organization, reproductive practices, and various other sociocultural factors. These disorders are mainly caused by mutations in monogenic, polygenic or the combination of gene mutations, consanguineous marriage practices, and environmental factors leading to damage of chromosomes. Nearly 7000 different types of rare genetic diseases/disorders are being discovered frequently. Cytogenetic and molecular techniques have been widely implicated to detect variations in the chromosomes and in genes. Several innovative and extremely robust methods for sequencing the nucleic acids such as next-generation sequencing have become available in the past few years for diagnosing chromosomal and genetic disorders. We have summarized the rare genetic disorders, their cytogenetic location, candidate genes, novel mutations identified, and advanced diagnostic tools that are currently being used for rapid detection of these abnormalities. The application of advanced technologies is rapidly changing the background of genetic research and also in clinical practice. The identification of novel disease-causing genes, mutations, and predisposing genetic variants data is getting into accelerated. The availability of huge genetic information will uphold a better indulgent of genetic disease etiology, permit early, even per-symptomatic diagnosis, and preventive measures to avoid the onset of the disease. This review will make clinicians/pediatricians to classify rare disorders with their genes responsible, leading for accurate genetic diagnosis.