Topic 1 facts Flashcards
Describe the ethical, economical and cultural issues with collection of genetic information
Genetic information collection problems
Potential for discrimination: There is a risk that insurance and prospective employers may discriminate on the basis of genetic health.
Ownership: The genetic information obtained from an individual should be the legal property of the individual.
Privacy and confidentiality: The results of the genetic test have the potential to be shared with other parties without the permission of the owner.
Emotional impact on the individual: The results of the genetic screening have the potential to be emotionally distressing and genetics counselling is required. Some genetic illnesses have no known cure or effective treatment.
Impacts on the family members. Genetic testing of an individual can also reveal genetic information about a person’s family. The potential emotional impact on family members be considered.
Impact on children: Genetic testing of an individual may be carried out during infancy at the request of the parents. The child did not give informed consent and may not wish to know their potential risk factors.
Social implications: The results of genetic testing have the potential to make an individual feel socially deprived, psychologically traumatised, or stigmatised by attitudes towards genetic differences.
Impact on reproductive choices: Knowledge that a prospective parent has a genetic disease may impact their decision to have children. This decision is normally influenced by individual, family, religious and cultural belief.
Limitations: Genetic testing can provide information about the nature of potential risk factors for genetic disease but rarely predicts the severity of the condition or age at which symptoms will onset. Environment is a factor in the development of genetic disease.
Inaccuracies: There is always a possibility that genetic information is inaccurate or is misinterpreted. The impact of a false positive or negative result from genetic testing could be devasting.
Reliability: The results of genetic testing may prove to be an unreliable indicator of developing a genetic disease. Longitudinal studies are required to asses the reliability of genetic testing in accurate diagnosis of genetic disease.
Benefits of CRISPR-Cas
Genomes can be edited more rapidly than in conventional techniques. Multiple genes can be edited simultaneously in the host genome.
Inexpensive technology (far cheaper than conventional methods of gene editing)
Gene editing is highly specific and accurate as the Cas9/gRNA complex identifies target nucleotide sequences with high specificity.
The gRNA sequence of the Cas9/gRNA complex can be altered to be complementary to any nucleotide in a genome.
Limitation of CRIPSR-Cas
Mutations in the target nucleotide sequence if the genome reduces the effectiveness of the Cas9/gRNA complex.
Cuts made by Cas9 can be repaired by enzymes before the genome can be edited.
Unwanted (off-target) mutations can if the target nucleotide sequence for the gRNA appears at multiple sites in the genome.
CRISPR/ Cas recognises short nucleotide sequences (24-48 bp). Shorter sequences are more likely to occur at multiple sites in the genome causing unwanted cuts.
CRISPR/Cas applications
Agriculture: CRISPR/ Cas has been used to insert disease resistance genes into plants.
Biotechnology: Modifying the genomes of yeast cells to synthesise chemicals called hydrocarbons that are used to make plastics.
Research: Scientists study the role of gene mutations in the onset and development of genetic diseases by using CRISPR/ Cas to create targeted mutations in certain genes.
Gene therapy: Gne mutations can be corrected using CRISPR/ Cas allowing scientists to remove mutations in oncogenes and tumour suppressing genes that are implicated in cancer.
Immunology: CRISPR/ Cas can be used to removeHIV DNA from the genome of an infected person which promises therapy and protection from HIV and most other viral infections.
Ethical concerns regarding CRISPR/ Cas
Accidental or deliberate release: Viruses are used as vectors to insert the CRISPR/ Cas9 package into the cells of a target organism in a laboratory setting. An airborne viral could escape the lab and enter the environment where it is inhaled by the human population. CRISPR/ Cas9 could then edit genes in human cells with unknown consequences.
Off-target editing: CRISPR can edit the genomes of organisms at unwanted locations (introduce harmful mutations) which reduces its effectiveness in medicine for the treatment of genetic disease and cancer.
Designer babies: Concerns have been raised about the use of CRISPR to edit germ cells in human embryos for the purposes of removing gene mutations for certain diseases. Some researchers have questioned whether CRISP will be used to develop genetically-superior humans.
