Down syndrome is a genetic disorder caused by an extra copy of chromosome 21, leading to changes in the physical and functional development of those affected. This disorder occurs due to a random error during cell division, where the extra chromosome accumulates in most cases due to a lack of parallelism in the proper separation of chromosomes during germ cell formation. As a result, the child inherits an extra copy of the chromosome, causing a range of physiological and intellectual effects, from mild to severe. In response to this condition, modern technologies such as CRISPR have become tools that enable genetic intervention to modify or correct defective or mutated genes. CRISPR technology involves targeting specific gene locations, allowing for precise modification of genetic material by cutting, repairing, or replacing genetic transcripts. This may open new avenues for treating genetic diseases, including Down syndrome. The application of CRISPR in removing the extra copy of chromosome 21 represents a significant advancement in genetic engineering, where gene-editing tools are used to enable the selective and safe removal of unwanted chromosomes. However, this process requires extremely precise handling, as errors in editing can lead to unforeseen results or damage at the cellular or tissue level. Furthermore, research in this area faces technical and biological challenges, including ensuring genetic privacy, minimizing the likelihood of errors, and developing effective methods to guarantee the sustainability of results. Despite these challenges, the use of CRISPR technology to remove the extra chromosome remains a promising option for achieving significant progress in the treatment of genetic conditions related to Down syndrome. Much future research and studies are expected to yield significant breakthroughs in this vital field. Down syndrome, also known as trisomy 21, is a genetic disorder resulting from the presence of an extra copy of chromosome 21 in an individual's somatic cells. Normally, humans have 46 chromosomes in two equal sets. However, in Down syndrome, there is an extra copy of this chromosome, resulting in 47 chromosomes instead of 46. This disorder is one of the most common genetic disorders, with an estimated 1 in 700 babies born worldwide. The extra chromosome affects the physical and mental development of those affected, causing distinctive signs and a variety of symptoms related to physical growth and intellectual development. This disorder occurs due to an error in cell division during gamete formation or in the embryonic stages, and the likelihood of its occurrence increases with maternal age, particularly after 35. Down syndrome is characterized by distinctive features, including specific facial features such as a flattened face, slanted eyes, and a small nose, as well as potential health problems such as heart defects, muscle weakness, and intellectual disability, which varies from person to person. The condition can be diagnosed during pregnancy using early screening techniques, such as ultrasound imaging and prenatal genetic testing. Early diagnosis is a crucial step in preparing care plans and implementing early intervention, which plays a vital role in improving the quality of life for those affected. Understanding the nature of this disorder is fundamental to developing treatment strategies and innovative technologies, including CRISPR technology. This technology allows for the modification of cells and genes to eliminate the genetic cause of the syndrome—the extra chromosome—thus reducing the health and social impact of this disorder on the individual and society. CRISPR technology represents a revolution in gene editing, providing a precise and efficient method for modifying the human genome. Its mechanism of action relies on using the Cas9 enzyme as a scissors, cutting DNA at the desired location, guided by specific RNA markers. This enables the precise targeting of chromosomes, including those that cause genetic syndromes such as Down syndrome. By designing specific RNA markers to target the extra chromosome, CRISPR technology can be used to selectively disable or remove it, reducing the risk of developing symptoms associated with complications resulting from the genetic duplication. The use of CRISPR in this context opens up significant therapeutic possibilities, as it can contribute to correcting genetic abnormalities before symptoms manifest permanently, or as part of gene therapy strategies. Despite its considerable potential, CRISPR applications for removing the extra chromosome face technical challenges related to ensuring the accuracy of the editing and preventing unintended cuts to healthy regions of the genome. Furthermore, laboratory processes and clinical trials require meticulous design to guarantee efficacy and achieve the desired outcomes. Therefore, developing improved targeting methods and repair facilitation techniques is a priority in advancing this field. It is worth noting that the results of preclinical studies and recent trials have shown promising signs, with successes achieved in laboratory models and some technical hurdles overcome. This makes it a promising prospect for the future treatment of Down syndrome through safe and effective removal of the extra chromosome. Adopting a strategy for removing the extra chromosome associated with Down syndrome requires the development of a precise plan based on gene-editing tools such as CRISPR technology. This strategy begins by precisely identifying the locations of the extra chromosome 21. Specially designed targeting systems are used to precisely target the specific regions of the chromosome responsible for the genetic duplication. The design of the RNA molecules is relied upon to enhance targeting accuracy, thus minimizing the possibility of unwanted interference with other parts of the DNA. After identifying the target sites, the CRISPR-guided cutting process is performed, in which a type of enzyme is inserted.