Population genetics-hardy weinberg equilibrium and non random matting

HWE- introduction, properties, criteria,problems and signification.
introduction, types and significant of non random matting.

1. HARDY WEINBERG EQUILIBRIUM
And
NON-RANDOM MATTING
NANDEESHA S
1st sem PLANT SCIENCE
BANGALORU CENTRAL UNIVERSITY
HCT 104 : UNIT IX

2. G. H. Hardy Wilhelm Weinberg
(1877-1947) (1862-1937)

3. Hardy weinberg equilibrium
Model named after the two scientists, describes and
predicts genotype and allele frequencies in a non-
evolving population.
THE allele and genotype frequencies in a population
will remain constant from generation to generation
in the absence of other evolutionary influence.
Dominant alleles do not in fact replace recessive
ones.

4. A population that is not changing genetically .
If there is no change in frequencies, there is no
evolution.
In fact, allele frequencies often change in natural
populations, with some alleles increasing in
frequency and others decreasing.

5. ALLELE FREQUENCY
Gene frequency-alleles are variant forms of a gene
that are located at the same position or genetic
locus on a chromosome.
GENOTYPE FREQUENCY
Genotype frequency-in a population is the
number of individuals with a given genotype
divided by the total number of individual in the
population.

6. oLarge population
oThere is no mutations of the alleles
oThere is no migration (no immigration or emig
ration)
oRandom mating
oNo natural selection
Populations In Hardy Weinberg
Equilibrium Meet
Five Criteria

7. 
Methods

8. Gene frequencies will be unpredictable in small
populations.
All the genotypes in a population reproduce
equally and successfully.
A population in Hardy-Weinberg equilibrium do
not show evolution.
Significance Of Hardy Weinberg
Equilibrium

10. 
Problems Based On Hardy Weinberg
Equilibrium

11. Non-Random mating

12. NonRandom mating the probability that
two individuals in a population will mate is
not the same
for all possible pairs of individuals.
OR
In a population male does not mating with
any female of population is called as non-
random mating.
most animal and select mates carefully they do not
mate randomly

13. Assortative-individual mate with other who are
like
themselves phenotypically for selected traits
(similar)
•in breeding (extreme) –close relatives
1
st
and 2
nd
,cousins
sibling
Types of non mating
random

14. Disassortative-individual only mate with others
who are phenotypically differ from themselvesFor sel
ective traits (opposites)

15. SIGNIFICANCE OF NON-RANDOM MATING
Plant and animal breeders usually employ controlled
positiveassortativemating to increase the
frequency of desirable traits and to reduce genetic
variation in a population.
This method has been used to develop purebred
varieties of laboratory mice, dogs, horses and other
farm animals.

16. Thank you