Mendelian Inheritance Flashcards
What is Mendel’s first law of inheritance?
Law of segregation
1 copy of allele per cell
what is Mendel’s second law of inheritance?
Law of independent assortment
other alleles do not affect the assortment of other alleles
what is classified as a mendilian disease?
single allele mutation will be passed on to kids in fixed proportions according to mendilian laws of inheritance (not due to effects from multiple genes)
what are the 2 factors that determine inheritance in single gene disorders?
- Quality of phenotype (dominant vs recessive)
2. location of the gene locus (autosomal vs sex chromosome)
what is penetrance?
you either have the gene or you don’t
On/Off switch on light
what is expressivity?
the severity of the disease
light dimmer switch, varying degrees of severity
what is pleiotropy?
when a gene affects multiple different organ systems
what is population genetics?
the distribution of genes within a population and how they change within that population
what is the purpose of the Hardy-Weinberg principle?
estimate genotype frequencies within a population when allele frequency is known
what is the equation for Hardy-Weinberg principle?
(p+q)^2 = p^2 +2pq + q^2
what does q^2 equal?
frequency of homozygous recessive individuals
what does p^2 equal?
frequency of homozygous dominant individuals
what does 2pq equal?
frequency of heterozygous individuals
what is the equation for calculating just the amount of dominant and recessive alleles when the frequency of one allele is known??
p+q=1
what are the 5 assumptions of Hardy-Weinberg Principle that must be present for the equation to work?
- No mutations
- No migration
- Large population
- random mating
- no natural selection
