Exam #5: Molecular Medicine I Flashcards
Direct Sequencing (Sample type & what it detects)
- DNA sample
- Detects point mutations/SNPs
Whole Exome Sequencing (Sample type & what it detects)
- DNA sample
- Detects point mutations/ SNPs in exons- not introns or intergenic regions
SNP Typing (Sample type & what it detects)
- DNA sample
- Detects SNPs in the entire genome
PCR (Sample type & what it detects)
- DNA sample
- Detects insertions or deletions
Reverse Transcriptase PCR(Sample type & what it detects)
- RNA sample
- Detects the expression levels of a small number of genes
Allele Specific Oligonucleotides (Sample type & what it detects)
- DNA sample
- Detects point mutations & small insertions/deletions
Gene Expression Array (Sample type & what it detects)
- RNA sample
- Detects expression levels of thousands of genes- not intergenic regions or introns
Methylated DNA PCR (Sample type & what it detects)
- DNA sample
- Detects epigenetic changes/ DNA methylation
Comparative Genome Hybridization (Sample type & what it detects)
- DNA sample
- Detects insertions, deletions, & aneuploidies in the kilo-to megabase range
FISH(Sample type & what it detects)
- DNA sample
- Detects copy number of a selected chromosomal region
ELISA(Sample type & what it detects)
- Protein sample
- Detects the amount of protein in a sample
Western Blot (Sample type & what it detects)
- Protein sample
- Detects the amount & size of protein in a sample
Direct Sequencing
Sequencing the genome for an exact mutation
Indirect Marker Analysis
When the error in the gene responsible for causing a disease has not been identified, “markers” are used to find out whether a person has inherited the region of the genetic code that is passing through the family with the disease. Markers are DNA sequences located close to the area of interest that are so close that they are almost always inherited together with the disease. When markers are this close to a gene where they are inherited together, they are said to be “linked.” In this way, if someone has the set of linked markers, he or she will also have the disease-causing gene. For this reason, these types of studies are also called “linkage studies.”
WGS
- Whole genome sequencing
- Not feasible or useful in the clinical setting
- Analyzing 3 billion base pairs
WES
- Whole exome sequencing
- Only 3% of the entire genome codes for exon sequences
- Sequences the exons only
SNP typing
- 99% of the DNA does not vary between individuals
- To learn about the genetic characteristics of an individual, look at the single nucleotide polymorphisms only (the different stuff)
What is the importance of copy number?
- Individuals don’t just vary by single nucleotide polymorphisms, but also by small insertions/deletions of the chromosome (i.e. duplication of a gene on a chromosome)
- This phenomenon is referred to as copy number variation