DNA sequencing and personalised medicine

Question 1

Whast are the 4 steps of NGS

Answer 1

DNA fragmented and adaptor molecules added to ends
Cluster generation - each fragment hyrbridised to solid plate
Sequencing - labelled dNTPs added, each binding produces flash of light, then done backwards
Data analysis - forward and backward reads are combined and sequence is constructed

Question 2

How does NGS differ from sanger sequencing?

Answer 2

Higher sensitivity to detect low-frequency variants
Faster turnaround time for high sample volunes
Comprehensive genomicv coverage
Lower limit of detection
Higher throughput with sample multiplexing
Sequence hundred of thousands of genes/regions simultaneously
More expensive

Question 3

How is NGS varied to determine the molecular basis of monogenic diseases?

Answer 3

Rapidly sequences DNA fragments
Targeted - sequences specific gene to identify mutation
Epigenome - uses bisulphite to show methylated regions to identify impact of disease
Transcriptone - Converts mRNA to cDNA to sequence transcribed proteins, if transcribed but not present in protein form = problem with translation/folding

Question 4

Define precision medicine

Answer 4

Use of genomics to tailor medical care to individuals based on their genetic makeup

Question 5

What are 5 possible uses of precision medicine?

Answer 5

Discovery - mechanisms and biomarkers of diease
Diagnosis - identification of pathology/condition
Classification - staging and classification of disease such as cancer
Prognosis - certain mutations may alter chance of survival
Therapeutics - different mutations respond to different treatments

Question 6

How can precision medicine be used in the treatment of cancer?

Answer 6

Clinical studies using genomes of cancer patients and non cancer patients can be sequenced to identify mutations for novel drug treatments