4-6-7 Application of Human Gene Science Flashcards
Some applications of human genome information
Detection of diseases
Treatment of diseases
Cystic fibrosis (CF): how is the disease inherited?
The CF allele is autosomal recessive: It is located in chromosome 7 (not on a sex chromosome), and both alleles need to have the CF mutation in order for the individual to have the disease.
How prevalent is CF in the Caucasian population?
The disease occurs in 1 out of 2,000 births among Caucasians. 4% of the Caucasian population are heterozygotes, meaning that one of the two alleles carry the CF mutation. The heterozygote individuals do not have the CF disease, but are carriers. The union of two heterozygote individuals will have 1 in 4 probability of producing offspring having CF mutation in both alleles.
How are genetic diseases detected before birth?
Fetal cells are collected using amniocentesis or chorionic villi sampling and analyzed for harmful alleles.
How is sick-cell disease diagnosed prenatally?
Sickle-cell disease is diagnosed prenatally by restriction fragment abnormality: The mutation destroys a restriction enzyme cutting site, changing the length and number of DNA fragments.
What is pre-symptomatic screening?
Some genetic diseases do not show up until later in life, such as polycystic kidney disease. Pre-symptomatic screening allows for the diagnosis of such genetic disorders in young individuals before the symptoms show up.
How is gene therapy different from taking medications?
Gene therapy involves the incorporation of a corrected gene into the cells of an individual with a genetic disorder.
How are corrected genes incorporated into the cells of individuals?
A vector, such as a virus, is used to carry the desired gene into the cell. The desired gene is inserted into the viral genome. The ability of the virus to cause disease is also deactivated. The virus then infects the patient and incorporates the desired gene into the patient’s DNA or cell.
Instead of infecting the patient with a recombinant virus carrying the desired gene, a different approach is…
to infect cells removed from the patient with the recombinant virus, then put the infected cells back in the patient.
