Mutation and Inheritance Flashcards
What is a mutation
A gene variant
What is evolution dependent upon
Advantageous mutations/variants
What is genetic disease the result of
Disadvantageous mutations/varaints
What is a single nucleotide variant (SNV)
A change of one base pair to another
What is a non coding SNV
A SNV outside of the protein coding region of a gene (intronic/intragenic)
What is a protein coding SNV
An SNV that is inside the protein the coding region of a gene (exonic)
Define synonymous
Does not change the amino acid
Define non-synonymous
Changes amino acid
Are synonymous or non-synonymous mutations rarer in the population and why
Non-synonymous due to their physical outcome decreasing the likelihood of the mutation being passed on as rare diseases are strongly selected against
What is a deletion mutation
Removal of section of DNA
What is an insertion mutation
An insertion of a section of DNA
What is a frame shift mutation
A mutation that alters the triplets and is disruptive if it occurs in the coding region
What are Gregor Mendel’s 3 laws
The law is segregation, the law of independent assortment, the law of dominance
What is the law of segregation
Each individual contains two alleles e.g. maternal and paternal as we are a product of two genomes
What is the law of independent assortment
Each allele is inherited independently of each other with no relationship between inheritance of chromosomes, so an individual ends up with a random mix of chromosomes
What is the law of dominance
Recessive alleles will be masked by dominant alleles
What are autosomal chromosomes
Non-sex chromosomes
What is the frequency of rare genetic diseases in the population
<0.0005%
What is the frequency of common genetic diseases in the population
> 1%
Are rare or common genetic diseases more likely to be familial
Rare
When does rare genetic disease onset
Manifests early in life and is usually catastrophic
What is the difference in the cause of rare and common disease
Rare is purely genetic while common is both environmental and genetic
Which type of disease is typically monogenic
Rare disease
Which type of disease is typically polygenic
Common disease
What is the Hardy-Weinberg equilibrium
Genotypes within a population will reach an equilibrium through random mating, so variants and allele frequencies follow a predictable pattern assuming no selection
What is Hardy-Weinberg dis-equilibrium
The genotype distribution becomes skewed or in disequilibrium if there is a selection pressure against an allele in the population
What is a scaled analysis
Analysis of millions of variants at a time where each is assessed for association with a disease and given a statistical link (p value) to being affected
What is nutrigenomics
Genome wide association (GWAS) used to locate variants associated to. ‘wellness’ e.g.variants that affect ability to metabolise vitamins that may put individuals at more or less of a risk if vitamin associated disease
