What is HIV?
HIV, which stands for Human Immunodeficiency Virus, is a pathogen that attacks and weakens the immune system. The virus targets CD4 cells, also known as T-helper or white blood cells, and uses those cells to make copies of itself. As more and more CD4 cells get destroyed, the immune system gradually weakens, making it harder to fight off infections over time. HIV is a sexually transmitted disease meaning it is not passed through sweat, saliva, or urine (Felman, 2020).
Stages of HIV
(Rees, 2019)
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Stage 1: Acute Primary Infection -At this stage, the amount of HIV in your blood is high, and you're more likely to pass the virus onto others -Some people develop flu-like symptoms due to their body's natural response to the virus Stage 2: Chronic HIV Infection (Asymptomatic) -HIV is still active but reproduces at low levels Stage 3: Acquired Immunodeficiency Syndrome (AIDS) -Immune system is severely damaged leading to opportunistic infection -AIDS occurs once the immune system is too weak to fight off infection (Nall, 2020) |
Why CRISPR? |
CRISPR, which stands for Clustered Regularly Interspaced Short Palindromic Repeats, and CRISPR-associated protein 9 (Cas9), are technologies used for genome editing. In comparison to other HIV gene editing technologies like zinc finger nucleases (ZFN) or transcription activator-like effector nucleases (TALENs), the CRISPR-Cas9 system is showing huge promise since it is faster, cheaper, and more accurate than the other methods. (What are Genome Editing, n.d.) |
(Heidt, 2020)
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How CRISPR WorksCRISPR is a genetic engineering system that uses guide RNAs (gRNAs) and the Cas9 protein to essentially change the host's DNA. The gRNAs are designed so they bind to a specific target sequence of DNA within a genome, while the Cas9 enzyme work to cut the DNA at that target location. This allows for the precise insertion, deletion, and replacement of certain, unwanted DNA sequences. (What are Genome Editing, n.d.)
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Ethical ChallengesThe term "CRISPR" has drawn both positive and negative attention, as the ethical debate regarding genome editing reveals some scientist's concerns. This is because unlike TALENs or ZFNs, the CRISPR/Cas9 system enables quick, efficient, and cheap gene editing that can alter whole genomes. This debate is mainly centered around the concern for changes made to genes of human germ cells and embryos since it could spur the idea of enhancing certain traits (intelligence, eye color, etc.), to create "designer babies" . (Caplan, 2015)
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(Collins, 2019)
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(Two-year old gene, 2020)
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