Male parents generally DO NOT Contribute cytoplasm to zygotes SO… mitochondria and chloroplasts...

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Male parents generally DO NOT

Contribute cytoplasm tozygotes

SO… mitochondria and chloroplasts are MATERNAL CONTRIBUTIONS

Cytokinesis( Cell Division)

- actin microfilaments

and Karyokinesis( Nuclear division, including mitosis)

-tubulin microtubules

Model for organelle divisionFrom Dec 2003 Science

..…without implications for segregation

Maternal effect )NOT Maternal inheritance(

Genetic/genomic imprinting

Maternal imprinting

Paternal imprinting

If neither copy of 15q11 has paternal imprinting, the result is Prader-Willi syndrome )characterised by hypotonia, obesity, and

hypogonadism .)

If neither copy has maternal imprinting, the result is Angelman syndrome )characterised by epilepsy, tremors, and a perpetually smiling facial expression( .

גנטיקה של אוכלוסיותגנטיקה של אוכלוסיות

Formula for allele frequency, based on knowledge of genotypes

A 3 allele case

p = freq of IB = freq B )IBIB( + ½ freq of B )IBi( + ½ freq of AB )IBIA(q = freq of IA … =r = freq of i… =

p + q + r = 1

In 3 allele case, same mathematical treatment

YET:Populations with different genotypes can have the same allele frequency

BUT, if there are random matings, the genotype frequency of offspring is based on solely on the allele freq.

In next generation

Hardy-Weinberg (H-W) Law

&)Chetverikov(

YET, if there are random matings, the genotype frequency of offspring is based on solely on the allele freq.

In this case:

In next generation

Hardy-Weinberg (H-W) Law

Populations NOT in H-W equilibrium

If the processes below do not occur, a population is in Hardy-Weinberg )HW( equilibrium, the following are unchanged:

Allele frequenciesGenotype frequencies

Phenotype frequencies

TEST: if these populations are in H-W equilibrium, then:

If a population is in Hardy-Weinberg equilibrium,

the allele,genotype, and phenotype frequencies will

be stable as long as the HW requirements hold

H-W בשיווי משקל -- הרבה אכלוסיותאז... תיאור של אכלוסיה לפי תדירויות

מתאים )ו'חסכוני'( - של אללים

Genotypefrequencies

2 allele case

Genotypefrequencies

M/M

M/N

N/N

p)M(q)N(

Percent

LocationMMMNNNpq

Iceland31.251.517.300.570.43

Greenland83.515.60.90.920.08

We see HW equilibrium for ‘breeding populations’

We don’t expect HW for, say: the city of New York City Lots of immigration

Not random matings, but many distinct sub-groups

How do HW populations “start” with different allele frequecies? In human populations, often small founder populations:

BUT, MANY human populations are in H-W equilibrium, for example- MN tables we just saw, and:

How do HW populations “start” with different allele frequecies? In human populations, often small founder populations:

Percent

LocationMMMNNNpq

Iceland31.251.517.300.570.43

Greenland83.515.60.90.920.08

If the processes below do not occur, a population is in Hardy-Weinberg )HW( equilibrium, the following are unchanged:

Allele frequenciesGenotype frequencies

Phenotype frequencies

If these processes DOoccur, the populations

change.-Each process can be

studied and quantitated

Selection of allele A: preferential survival

Haplotype

Inbreeding

0.5 X 0.5

Migrationללמוד בבית על

P is the allelic frequency in the donor population And p0 is the original frequency among the recipients

M-migration rate

Source of variation, deviation from HW:migration )M( into a population

OriginallyYamane – not resistance to Gefilte-fish

Poland – 0.42 are resistance to Gefilte-fish

Current- among Yamane 0.046 are resistance

Thus Ptotal 0.046-0 P-P0 is 0.42-0

M= 0.046/0.42=1.095

Inbreeding

Source of variation: deviation from HW:mutations have a slow effect on allele frequency )here, of w.t.(:

Pseudo male - female cross in neurospora

Jan 3 start

Allele names according to phenotype

Wild type

amorph

hypomorph

hypermorph

RR

RR

neomorph

R~

R~R~

R~

NULL

Standard Dominant – Recessive

Haploinsufficiency