5.1 Flashcards
How we relate DNA to a person
because of many polymorphisms in non-coding regions of DNA that make it unique and different TNTRs, we can show relatedness and identify individuals
Detecting SNPs (single nucleotide polymorphisms)
DNA microarray analysis
- complementary oligonucleotides (known sequences) are placed on microarray chip with variations for each possible SNP mutation
- fluorescently labelled DNA from individual is hybridized to chip
- can match fluorescent pattern (which squares light up) to which SNP person has since DNA will only bond to ON with the correct variations
Variable Number Tandem Repeats (VNTRs)
of tandem repeats can vary largely across individuals
- can be identified using PCR and gel electrophoresis (less pairs, shorter molecule)
- highly unlikely that unrelated individuals would have the same VNTRs
Phenotype vs Genotype
how the genetic variation presents itself (if at all) vs the genetic variation itself
Sickle cell anemia genotype
Chromosome 11, gene for beta globin protein, HbA allele - normal b-globin gene, HbS allele - sickle cell anemia gene
HbA/HbA - no sickle cell
HbA/HbS - no symptoms, can produce both proteins
HbS/HbS - sickle cell
homozygous vs heterozygous
two of the same alleles vs two different alleles
advantages of sickle cell mutation
heterozygous individuals have a resistance to malaria infection
effect of gene copy numbers on phenotypes
eg: more AMY1 copy numbers found in individuals with ancestors that had high starch diets