Chapter 14

Question 1

Recombinant proteins, adv?

Answer 1

those expressed by recombinant DNA
• High level of purity and quality
• Reliability of supply
• Consistency of quality

Question 2

How to clone genes

Answer 2

Isolate the gene of interest and its DNA base sequence
Recognition site for a restriction enzyme at its ends, as wells as those of the plasmid
Find a suitable plasmid- Ampr and lacZ (blue-fail)to isolate the ones which have successfully formed rec plasmids
Select host cell- replicate rapidly, E.coli, yeast and eukaryotic if protein is a glycoprotein
Extract protein from bacteria

Question 3

Genetic screening

Answer 3

Genetic screening- testing of a population to identify individuals who are at risk of a genetic disease or transmitting a gene for a genetic disease
severe or widespread disorder, reliable test, and effective treatment plan for the disorder

Question 4

Genetic testing

Answer 4

Genetic testing- screening of an individual to find out whether they are at an increased chance or have an inherited disorder
Diagnose a disease, scan newborns for inherited diseases

Question 5

Advantages and disadvantages of genetic testing/screening

Answer 5

People are informed of their health status, take pre-emptive steps to diagnose any inherited diseases
Know in advance if they can pass a defective allele to their child, and use prenatal or presymptomatic
Removes stress as it ensures parents that their child is healthy

Anxiety and stress if the embryo is positive for and inherited disease, deciding its fate
Disclosure of test results to third parties (insurers, employers) or family members who might find out they too have the disease

Question 6

DNA profiling

Answer 6

uses hypervariable regions of DNA- short tandem repeats (NON-CODING) which are unique to the one person (except for identical twins)
STR’s- hypervariable region of chromosomes where 2-5bp are repeated over and over
DNA of STR is amplified using PCR and separated using fluorescent dyes
DNA profile- series of coloured peaks at different locations (each peak an allele of an STR, length indicates number of repeats)
DNA profile based on many STR and Amel can be used to correctly identify the individual which the sample used came from, with a high probability (1 in a billion chance)

Question 7

DNA databases
issues?
used for?

Answer 7

stores DNA profiles of individuals convicted of serious crimes
Full match, partial match, familial search (lead)
Subjective (who to include) and discriminatory as DNA database identifies a person based on their criminal relatives

* Forensic investigations- solve cases, justice is more likely to be carried out, guilty is proved guilty, clear innocent people of wrong charges
* Identification of human remains (soldiers, aeroplane crashes)
* Paternity testing