Lecture 26 Flashcards
Personal Genomics
concerned with the sequencing and analysis of the genome of an individual
- employs different techniques
- -SNP analysis
- -exome or full genome sequencing
then genotype can be compare with the published literature to determine likelihood of trait expression and disease risk
Predictive Medicine
the use of the information produced by personal genomics techniques when deciding what medical treatments are appropriate for a particular individual
ex. inherited medical genomics, cancer genomics, and pharmacogenomics
Precision medicine
focused on a new taxonomy of human disease based on molecular biology
What are some examples of genetic testing?
- Newborn screening
- Diagnisti testingn
- CArrier testing
- Predictive testing
- Pre-symptomatic testing
- pharmacogenetics
newborn screening
targeted tests for recessive genetic disorders
ex. CF, sickle cell anemia
diagnostic testing
confirmatory test or differential diagnosis testing for a symptomatic individual
ex. skeletal dysplasias
carrier testing
targeted testing for asymptomatic individuals potentially carrying one or more recessive mutations
ec. Cf, Tay-Sachs
Predictive testing
tests for variants causing or associated with disease or disorders with a hereditary component, usually with adult onset symptoms
ex. most cancers, cadiovascular disease, diabetes
Pre-symptomatic testing
tests for variatnts causinf or associated with disease or disorders known to be inherited in the family, often with adult-onset symptoms
ex. huntington’s, alzheimer”s
Pharmacogenetics
targeted tests for variants associated with pharmaceutical dosage choise or adverse reactions
ex. DNA tests, warfarin, carbamazepine
What can be used to evaluate the validity of genetic tests?
- analytical sensitivity
- analytical specificity
- clinical sensitivity
- clinical specificity
- positive predictive value
- negative predictive value
- clinical utility
- personal utility
analytical sensitivity
refers to the proportion of assays with the genotype that have a positive test result (false-negative rate of the assay)
analytical specificity
refers to the proportion of assays without the genotype that have a negative test result (false-positive rate of the assay)
clinical sensitivity
refers to the proportion of people with a disease who have a positive test results (false-negative rate of diagnosis)
clinical specificity
refers to the proportion of people without a disease who have a negative test result (false-positive rate of diagnosis
positive predictive value (PPV)
refers to the likelihood that a patient has the disease given that the test result is positive
negative predictive value
refers to the likelihood that a patient does not have the disease given that the test result is negative
clinical utility
refers to the value of the test for determining treatment, patient management and family planning
personal utility
refers to the value of the test for personal and family choices
23andMe
a privately held personal genomic and biotech company based in Mountain View, CA
- named for the 23 pairs of chromosomes in a normal human cell
What are some examples of tests carried out by 23and Me?
36 genes tested for carrier status CF
- cancer
- sleep movement
- Ancestry
- shared family segments
What does 23andMe analyze and with what technology?
uses Illumina HTS iSelect HD
- scans for ~600,000 SNPs
What is Promethease?
- a literature retrieval system that builds a personal DNA report based on the scientific literature cited in SNPedia and a file of genotype (DNA) data
- customers of DNA testing services can use it to retrieve published data about their DNA completely independent of whichever company produced the data
Why do genetic sequencing companies need to use Promethease?
in 2013, the FDA instructed 23andMe that they could not report outcomes with medical relevance unless they had FDA approval
- so it does what the companies essentially cannot
SNPedia
a report that you can get from Promethease if you want more information about the SNP in question
What kind of reports can you get from promethease?
- sequence variants with bad outcomes
- lymphoma potential
- Prostate cancer
- Cancer
- rare pharmacogenomic variants
Why is 23andMe terrifying?
- real goal to hoard data?
- meant to be a front end for a massive information-gathering operation against an unwitting public
- –not the intention to be a medical device
- they reserve the right to use your personal information —including your genome- to inform you about events and try to sell you products and services
- attempts to recruit people who suffer from certain disease, such as Parkinson’s and a few types of cancer. simply though brute-force pattern matching
- –company has a chance of finding genetic causes of these ailments
