Notatki Danniego part 7 Flashcards
Inbreeding coefficient equation
f= EN (1/2)^n
f- inbreeding coefficient
N - number of paths
n - number of ancestors in the loop
In previous cause, 2 paths, red and blue
/// Wstawić schemat ///
Brocher collie (?) inbreeding from 1930
- > bred from best collies (Dad with daughters, granddaughters…)
- > congenital myopathy passed on, hidden recessive allele
- > double recessive results in muscle atrophy / death in early life
Polymorphic Anion afer (slugs) (?)
- Hermaphrodite, self-fertilisation (rarely)
- Lots of inbreeding (extreme inbreeding - self-fertilisation)
- Very little variation
- Self-fertilise more up (?)
- > all black in Scotland
- > environment is always the same, preferable characteristics are maintained in self-fertilisation
VLINCLI in finland
- Finland has 33 recessive disease that are unknown anywhere else in the world. This is one of them
- > result of inbreeding
- > traced back to a man in 1691 - Over time, inbreeding brings rare alleles together
Also an issue with British Pakistani population in England
- double child mortality rate of Northern Europeans
Sequencing Y chromosome
- Mostly pseudo genes
- Lots of repeated sequences
- Doesn’t really recombine, only tips sometimes
- 3 million bp palindrome
- Rest is filled with inter (?)/ Ψ genes/ errors
- Also has mutation repair mechanism
SRY binds to DNA and distorts shape and regulates genes that control development of testes
High mutation rate => 1/15 man infertile/ subinfertile due to deletion on the Y chromosome
Lamda people (?)
- 5ens (?) that migrated to south Africa
- Say they built Solomons temple - not true
- Lamda share Y chromosome haplotype with Coheroim (?), who descend from a group of junior priest from the temple (?
70% of Spanian men (?) have genes that originated from middle east
-> Arabs moved to Spain - 2000 years ago and left over 500 years ago
Rare surnames (Attenborough) share Y chromosomes
k.
Variegated leaf- patterns of green & white
Mirabilis:
-> Main sheet variegated
-> Some all green branches
-> Some all white branches
- Take cuttings
Egg Pollen Progancy (?)
1. White Green White
2. White Variegated White
3. Green Variegated Green
4. Variegated Green Mix. of green
5. Variegated White White & variegated
- , 2., 3., -> Maternal inheritance
- , 4. -> Chloroplasts inherited -> endosymbiosis
Neurosperm (bread mould) (?)
- crossed fokery (?) (flow growing) & normal strain
- > maternal inheritance
- > new strain grew slowly, mitochondria from maternal fokery strain
Chamydomonas moewusii (?)
single cell alga with flagella ~ 10nm
MT+ - with mitochondria:
MT+ Parent MT- Parent Offspring
resistant Sensitive All resistant
sensitive Resistant All sensitive
Chamydomonas moewusii (?) cont
- ABC & abc
- Changes in order of offspring
- Circular DNA in mitochondria
- Endosymbiosis
- Only 16,630 bp left in mitochonrial DNA as has moved to cytoplasm (?)
Pathogens can invade eggs of ladybirds/butterflies
- kill males or get females to eat males
- because they’re only passed on down maternal line like mitochondria so don’t need males
- mitochondrial disease
Mitochondrial disease pedigree
- Passed through mothers only (matrilineal to sons and daughters (?) )
- only daughters can pass on
- mostly deletions, smaller mitochondrial DNA will replicate more quickly and take over
As someone ages, …. mitochondrial deletions & …. likely to develop disease
more & more
more
- > muscle weakness
- > dropping eyelids
3 parent child:
- mitochondrial DNA from a healthy female to the mother & father
Population genetics:
Replace letters A and a in Mendel’s first experiment with numbers
0.5A 0.5a
A 0.5 0.25 0.25
a 0.5 0.25 0.25
*0.5 is the proportion of alleles that one big A little a (?)
Can change frequencies to be % of population
0. 8 0.2 0. 8 0.64 0.16 0. 2 0.16 0.04
This is looking at a population now, not just one family
General square + Hardy Weinberg equation:
General square:
p q p p^2 pq q pq q^2
Hardy Weinberq equilibrium
p^2 + 2pq + q^2
(when p+q = 1)
2 shipwrecks, 1 with 60 normal AA and another with 40 albinos aa (assume random mating)
=> 200 alleles total; 120 copies of a; 80 COPIES OF A
frequency of A = p = 120/200 = 0.6
frequency of a = q = 80/200 = 0.4
Hardy Weinberg after I generation:
AA Aa aa
p^2 2pq q^2
0.36 0.48 0.16
frequency of A = 0.36 + (0.48/2) = 0.6
frequency of a = 0.16 + (0.48/2) = 0.4
Allele frequencies haven’t changed but phenotype frequency does!
This equilibrium will stay the same now unless something comes to change it
-> movement/mutation
Max heterozygosity (2pq) is at p = 0.5 and q = 0.5
What change a pop from H.W?
1)
1) Genetic drift and bottlenecks (random change)
- > Sampling error x genetic drift: the standard deviation of a population:
Sqrt of (pq/N) where N=number of individuals that reproduce
-> Shift is greatest when pq is large (p=q=0.5) or when N is small
Inevitable that genetic drift will cause a population to diverge phenotypically/genetically
k
The Harmonic Mean is bottlenecks (?)
- Harmonic Mean over K generations
N1 generation I and so on:
K/ (YN1 + YN2 + …. 1/NK)
(?) FLUCTUATING POP: 100…
Arithmetic mean is 802 (4010/2)
Harmonic mean is 48
Amish
(?)-What change a pop from H.W?
~ 400 Amish moved to U.S.A. - religous isolate
in 1850 existed in small, isolated colonies
By 1990 had grown exponentially
-> have families average of 8 children
-> 2014: 220,000 Amish
- Have unique genetic diseases prevalent now
-> Ellis - Van - Crevald syndrome
Similar on Tristan da cunks (?)
- > Started with pop of only around 5 people, by 1960 had pop of ~ 200
- > gene for retinal blasphema (eye cancer) present in one of the original settlers
- > this population has highest frequency of this gene in the world
Change to H.W?
2) (?) Migration
What change a pop from H.W?
3) Positive assortive mating (like with like) (?)
3) Positive assortive mating (like with like)
Rhagoleths pumonella - Apple muggot fly - NA
- > Used to feed on howthorne (?) - > Moved to apples - > Now choose to mate with flies that grew up on same plant - > Preference for scents - > Also mate at different times of year - > Has evolved this preference over just 100 years - Only mate with members of their species that are similar - In humans can be seen 'interacial marriage' - > Admixtune (?) - Or seen in educational level - > 6-7x move likely to marry someone who didn't finish high school if you didn't finish high school - > This effect has a greater effect now than interracial preference
