tech and health - genetics related tech

Question 1

traits

Answer 1

• may be inherited (ex. one can roll tongue and other cant)
• may come from interaction between inherited features and environment

epigenetics: how your behaviour + environment (stress, alcohol, smoking) can change/ affect the way your genes work

the ways genetics and environment interact to produce a trait: chances of getting cancer depends on both family history and lifestyle

Question 2

mutations

Answer 2

random events that change the sequence of a gene and create a new allele (can produce a new trait, new traits is important in evolution)

Question 3

inherited disease

Answer 3

some diseases are:
- hereditary (run in family: CF, ablanism)
- caused by environment (infectious diseases)
- combination of hereditary and environmental factors (alzhimers, diabetes, MS, dementia)

Question 4

genetic disorders (single-gene defects)

Answer 4

caused by a single allele of a gene, inherited in families (Huntingtons, CF, hemophilia, sickle cell anemia, Duchenne muscular dystrophy)

CF:
caused by mutation in single gene CFTR (single allele)

recessive trait (can be a carrier, but to have CF you need both recessive alleles) (1/4 children when parents are both carriers)

Question 5

other diseases

Answer 5

influenced by genetics, but the allele a person gets from their parents only changes their RISK of getting disease (inherited in complex way involving multiple genes, or both genes and the environment)

Breast cancer:
risk of breast cancer is 50x higher in families most at risk compared to families least at risk due to number of alleles which each change the risk a little bit

risk of breast cancer is a result of a large number of alleles AND her environment, so very hard to predict

Question 6

1. genetic engineering (genetic modification)

Answer 6

uses lab-based technologies to ALTER DNA MAKEUP of an organism

ex. changing single base pair or deleting/ adding segments of DNA

led to production of medically important products:
- human insulin
- human growth hormone
- hep B vaccine
- genetically modified organisms such as disease-resistant plants

Question 7

2. vaccines

Answer 7

on poster

Question 8

3. gene transfer therapy

Answer 8

insertion of genes into an individuals cells and tissues to treat a disease, and hereditary diseases where a defective mutant allele is replaced with a functional one

ex. CFTR gene provides instructions to make CFTR protein (mutations in CF gene = CF)

Question 9

types of gene therapy

Answer 9

germ line therapy:
- germ cells (sperm or egg) are modified by introduction of functional genes, which are integrated into their genomes and ALL CELLS ARE TARGETED

• HERITABLE - passed onto later generations
  
  • therefore should be effective in counteracting genetic disorders! (but prohibited in humans right now)

somatic gene therapy:
- somatic (body) cells are modified by introduction of therapeutic genes, ONLY SOMATIC CELLS TARGETED (SPOT)

• NOT HERITABLE - restricted to individual only

Question 10

viral vectors

Answer 10

adenoviral

retroviral

lentiviral

adeno-associated viral

Question 11

retroviruses

Answer 11

RNA that uses viral reverse transcriptase enzyme to transcribe RNA into DNA that replicates within host cell (HIV that can lead to AIDS)

Question 12

adenoviruses

Answer 12

double stranded DNA

cause respiratory, intestinal, and eye infections (common cold)

this vector system has shown promise in treating cancer, it’s the first gene therapy to be licensed to treat cancer

Question 13

MILESTONES in gene therapy

Answer 13

1866 - Gregor Mendel with peas (heredity)

2007 - first gene therapy trial for inherited retinal disease

2007 and 2008 - Hutter cured a man with HIV with repeated hematopoietic (blood) stem cell transplantation with a CCR5 mutation
- carriers of CCR5 mutation are resistant to certain strains of HIV

2011- cure for HIV accepted (requires complete removal of bone marrow)

2012 - first gene therapy in western world to reach recommended regulatory approval (glybera gene therapy for genetic disease LPLD)

2017 -2019 - first gene therapies approved in US (gene therapies are only recently approved)

Question 14

4. genome editing (eg. CRISPR-Cas9)

Answer 14

CF: CRISPR cuts out and replaces/ repairs defective part

ethical issues:
1. safety
- offtarget effects and (edits in wrong place) and mosaicism (some cells carry edit and others do not)

2. informed consent
   - impossible for germline therapy and PGD with IVF
3. justice and equity
   - only for wealthy?
4. genome-editing research involving embryos
   - moral and religious objections to use human embryos for research