Personalized Genomics

Question 1

personalized genomics

Answer 1

Scans of healthy individuals genomes to create personalized risk profiles for multiple health conditions and using the info to enable individuals to take precautions before their negative health outcomes

Question 2

Uses of personalized genomics

Answer 2

1. Primary Prevention: Testing that leads to decreasing the number of people born with that disease (Carrier testing and prenatal counseling)
2. Secondary Prevention: Testing that leads to early disease detection and interventions (Newborn screening, cancer genetics)
3. Tertiary Prevention: Testing that leads to personalized treatments (e.g., pharmacogenomics) (Which drug for which person? Efficacy (dose required) and side effects)
4. Quaternary Prevention: Testing that leads to improved psychosocial quality of life (Huntington disease)

Question 3

Why are hereditary cancer predisposition important?

Answer 3

1. detection at an early, curable stage
2. Targeted chemoprevention
3. Prophylactic surgery may be useful in conditions where the main risk of death relates to one organ and there is no effective surveillance

Question 4

Examples of targetted chemoprevention that was useful after genetic testing?

Answer 4

1. Estrogen antagonists decrease breast cancer risk in BRCA1 and BRCA2 carriers
2. Dietary management and non-steroidal anti-inflammatories decrease risk of colon cancer in Lynch syndrome

Question 5

Example where Prophylactic surgery was useful after genetic testing?

Answer 5

Thyroidectomy to prevent death from medullary thyroid cancer in multiple endocrine neoplasia type 2

Question 6

Genetic architecture of human disease

Answer 6

1. Mendelian disease (single gene trait runing in families) -> large effect size, rare
2. Sporadic disease, rare varients, substantial effect size -> medium effect size, medium frequency
3. common disease, common variant, small effect size -> small effect size, common

Question 7

Common variant, common disease

Answer 7

common diseases from multifactorial with small effects from many common variants and environmental factors

• Very few common diseases are explained, at a population level, by common single-gene variants (but every rule has exceptions—see macular degeneration and the CFH gene)

Question 8

Rare variants and common disease

Answer 8

some common disorders can be attributed to many different rare variants
skin cancer is associated with rare variants of MC1R

Question 9

Methods used in personal genomic testing

Answer 9

1. Multiple tests of individual, medium to high-impact susceptibility genes
2. Genome-wide SNP arrays
3. Whole genome sequencing

Question 10

Which methods used in personal genomic testing is clinically useful?

Answer 10

Multiple tests of individual, medium to high-impact susceptibility genes

Question 11

How do we find the genes underlying common traits?

Answer 11

Genetic Association Studies