Personal Genomics Flashcards
What is personal genomic information?
Any information generated by sequencing and analysing a person’s genome.
What are SNPs?
Single nucleotide polymorphisms.
SNPs are normal variations in bases the human genome.
Key role in disease development, response to treatment.
SNP profiling to accurately determine risk of developing disease.
Genome Wide Association Studies (GWAS) identifies the association of SNPs with disease in the population.
Where can genomic testing be used?
Diagnoses of rare diseases.
Identifying host genetic factors in multifactorial diseases.
Diagnosis of infectious diseases.
Diagnosis / treatment of cancer.
Pharmacogenomics.
Development of new drugs based on genomic targets.
New diagnostic tests.
What is Huntington’s disease?
Monogenic inherited disease that causes progressive degeneration of neurons in the brain.
Disease caused by excessive CAG repeats in the Huntington gene.
Normal alleles have 15-25 repeats, but >39 CAG repeats causes disease.
Test involves amplification of the huntington gene by PCR.
What is Array CGH?
Array Comparative Genome Hybridisation.
Diagnosis of diseases caused by chromosomal abnormalities e.g. Downs syndrome, Prader-Willi syndrome.
Patient genome compared to reference genome.
Fluorescence ratio indicates duplication or deletion of parts of the genome.
Explain BRCA 1 / 2 genetic testing:
BRCA1 and BRCA2 genetic variants associated with breast and ovarian cancer.
Variants could be inherited indicated by strong family history of cancer.
Predictive genetic test to predict risk of developing breast or ovarian cancer and managing this risk.
Test involves PCR amplification and DNA sequencing of these genes.
What is glaucoma?
Progressive neurodegeneration of optic nerve leading to blindness.
Diagnosis is usually too late as early stages are asymptomatic.
Highly heritable.
Most genetic contribution is polygenic.
GWAS have identified >100 common SNPs associated with glaucoma.
How does point-of-care testing work for SNPs?
Requires:
Amplification directly from blood.
A method of detection that makes use of single base difference between alleles.
Interpretation of the outcome.
