Genetic variation and Treating genetic disease Flashcards
what is human genetic variation
- This is the genetic differences both within and among populatiosn
what is genetic variation caused by
- There may be multiple variants of any given gene in the human populations leading to polymorphism/mutation and alleles
What is new variations and new mutations due to
- New mutations are due to shuffling of parent genes during sex
what type of variation are there
- variation in how we sense things and communicate
- why we are prone to certain diseases
- height
- eye colour
- skin colour
- hair loss
- no nails
what are the facts about the genome
- 21000 genes in the human genome that code for protien (1.5% of the whole genome)
The rest includes - DNA transcribed to form RNA molecules which are not translated into protein such as non coding RNA and miRNA
- Evolutionarily conserved non-coding regions, enhancer functions, transposons and microsatellites
what is single gene disorders
- Mutation in a single gene leading to disease
what are transposons
this is a DNA sequence that can change its position within a genome which can create or reverse mutations and alter the cells genetic identity and genome size
what are microsatellites
this is a set of short repeated DNA sequences at a particular locus on a chromosome which vary in number and different individuals and so can be used for genetic fingerprinting
name an example of a single gene disorder
cystic fibrosis
give 4 types of genetic disorders
- single gene disorders
- chromosomal disorders
- polygenic disorders
- somatic disorders
what do chromosomal disorders happen
- A change, gain, loss or exchange of chromosome elements
what is a polygenic disorder
- Due to the combined effects of many genes or in combination with environmental factors
what is a somatic disorder
these are disorders of the Body cells that happen during early development
describe an example of a chromosomal disorder
Turner syndrome
describe an example of a polygenic disorder
diabetes
describe an example of a somatic disorder
cancer
what is a splice site mutation
- Leads to an insertion or deletion of a number of nucleotides in the specific site at which splicing of an intron takes place - this may mean that the intron is not taken away from the gene or the exon can be deleted
How do you detect DNA variation
- Polymerase chain reaction
- sequencing
describe the polymerase chain reaction process
- denature the DNA do this by heating at 94 degrees at 1 minute
- anneal - foward adn reverse primers are added and you spend 45 seconds at 54 degrees
3, extension - this is when Taq DNA polymerase and dNTPs add nucleotides to it - repeat this many times then analyse it, add a floursent dye in it