Abstract

A REVIEW ON THE JUNK DNA AND DISEASE ASSOCIATED WITH JUNK DNA

Naresh Choudhary*, Parin Choksi and Rajashree Mashru

Abstract

Many years ago, scientist were trying to reveal number of different coding and non-coding regions. Coding regions are responsible for the protein synthesis while non-coding regions are portions which does not involve in protein synthesis. The scientists referred these regions (noncoding regions) as a Junk DNA. In 2001, human genome sequence discovery showed that there is 98% of Junk in our DNA. These noncoding portions are removed by post transcriptional modifications via Splicing mechanism. Splicing mechanism plays an important role in splice out the unnecessary portions from the pre-mature mRNA which is produced by transcription process. Disturbances in splicing mechanism leads to various genetic disease i.e., Spinal Muscular Atrophy is a bunch of inherited disorder characterized by a loss of certain nerve cell located in the spinal cord called Motor neuron. Fragile X Syndrome is majorly associated with intellectual and emotional disabilities i.e., learning problems to mental retardation, unstable mood swings and autism. Dyskeratosis Congenita is characterized by bone marrow failure syndrome causing abnormal skin pigmentation, with increased risk of squamous cell carcinoma and haematological neoplasms. Duchenne Muscular Dystrophy, mutation is takes place in gene which is responsible for production of dystrophin and it plays a role to connect the actin cytoskeleton with the extracellular matrix. Alzheimer’s disease, a progressively and neurodegenerative disease – is the most usual form of dementia with high incidence in elderly people.

Keywords: Junk DNA, Spinal Muscular Atrophy, Fragile X Syndrome, Dyskeratosis Congenita, Duchenne Muscular Dystrophy, Alzheimer’s Disease.