CRISPR

Imagine a future where genetic anomalies can be precisely targeted and corrected using genome editing – a giant leap from our ability to sequence or read human genomes two decades ago. The world of medicine is currently abuzz with news of regulatory agencies’ approval for two highly anticipated CRISPR-based therapies for sickle-cell disease and -thalassaemia in the U.K. and the U.S. The approval is groundbreaking because it signals an era that could transform the lives of millions of patients and families grappling with these inherited blood disorders. To put this in perspective, more than a million people worldwide suffer from thalassemia, of whom 100,000 depend on regular blood transfusions. Another 20 million people around the world are estimated to be suffering from sickle-cell anaemia

2. About CRISPR

• The journey to uncover the CRISPR system spanned nearly thirty years of dedicated academic pursuit. Initially identified in 1993 by Spanish researchers in archaea, these DNA elements, known as Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR), were later observed in various bacterial genomes.
• Comprising genetic material fragments from viruses attacking bacteria, along with CRISPR-associated proteins known as Cas, these elements intrigued researchers aiming to comprehend their impact on antiviral immunity. By 2005, it became evident that the collaboration between CRISPR and Cas proteins formed a defensive system in bacteria, enabling them to resist viral infections.
• The pivotal breakthroughs occurred subsequently: in 2010, scientists demonstrated that CRISPR, when paired with specific Cas9 proteins, possessed the capability to precisely cut double-stranded DNA at defined points.
• They also unveiled RNA molecules guiding Cas9 to specific positions within a genome. Further progress emerged in 2012 when researchers devised synthetic RNA that could bind to Cas9, directing it to edit DNA at specified locations.
• Emmanuelle Charpentier and Jennifer Doudna led this groundbreaking research, earning the 2020 Nobel Prize in Chemistry for their contributions. Shortly after, Virginijus Siksnys and colleagues published similar findings, proposing that Cas9 could be guided to specific genome spots by CRISPR RNA.
• Collectively, these studies showcased the CRISPR-Cas9 system's potential as a customizable 'molecular scissor,' precisely cutting DNA at designated spots. Altering the crRNA enabled scientists to target specific genomic locations accurately. The subsequent year, teams led by Feng Zhang and George Church demonstrated the use of CRISPR-Cas9 for genome editing in eukaryotic organisms.
• This innovation sparked a multitude of applications, from targeted genetic therapies to advancements in agriculture. The 2020 Nobel Prize not only recognized these researchers but also marked the onset of an era where manipulating human genetic code went beyond reading, potentially revolutionising medicine and genetic engineering