hardy weinberg genetic equilibrium by kk sahu

INTRODUCTION
HISTORY
THE HARDY-WEINBERG LAW
DERIVATION
TERMINOLOGY
PROBLEMS
ASSUMPTION OF HAEDY –WEINBERG EQUILIBRIUM
REFERANCE
The Hardy–Weinberg principle, also known as the Hardy–Weinberg equilibrium, model, theorem or law.
States that allele and genotype frequencies in a population will remain constant from generation to generation in the absence of other evolutionary influences.
These influences include mate choice, mutation, selection, genetic drift, gene flow and meiotic drive.
Because one or more of these influences are typically present in real populations, the Hardy–Weinberg principle describes an ideal condition against which the effects of these influences can be analyzed.

1. THE HARDY -WEINBERG GENETIC EQUILIBRIUM By KAUSHAL KUMAR SAHU Assistant Professor (Ad Hoc) Department of Biotechnology Govt. Digvijay Autonomous P. G. College Raj-Nandgaon ( C. G. )

2. SYNOPSIS :- INTRODUCTION HISTORY THE HARDY-WEINBERG LAW DERIVATION TERMINOLOGY PROBLEMS ASSUMPTION OF HAEDY –WEINBERG EQUILIBRIUM REFERANCE

3. Introduction:- Hardy-Weinberg equilibrium provides a framework for understanding how populations evolve.

4. Godfrey Hardy (1877-1947), an English mathematician, and Wilhelm Weinberg (1862-1937), a German physician, both found a way to link genetic probability and evolution in the early 20th century. Hardy and Weinberg independently worked on finding a mathematical equation to explain the link between genetic equilibrium and evolution in a population of species.

5. The Hardy – Weinberg Law was formulated independently by G.H.Hardy and Wilhelm Winberg in 1908. The genotype frequencies can be predicted from the allele frequencies. William Castle Godfrey Hardy

6. Hardy–Weinberg principle :- The Hardy–Weinberg principle , also known as the Hardy–Weinberg equilibrium, model, theorem or law. States that allele and genotype frequencies in a population will remain constant from generation to generation in the absence of other evolutionary influences. These influences include mate choice , mutation , selection , genetic drift , gene flow and meiotic drive . Because one or more of these influences are typically present in real populations, the Hardy–Weinberg principle describes an ideal condition against which the effects of these influences can be analyzed.

7. Mutation Gene Flow Non-random mating Genetic Drift Selection

8. Terminology Selection:- Selection is the process by which heritable traits that make likely for an organism to survive and successfully reproduce become more common in a population over successive generation. Mutation :- Mutation are changes in the DAN sequence of a cell genome and are caused by radiation ,mutagenic , viruses ,chemical as well as error that occur during meiosis or DNA replication.

9. Gene Flow :-Flow to alleles -Emigration and Immigration of individuals. Genetic Drift :-Random change in allele frequencies due sampling error. Big small Allele Frequency:-Allele frequency is how common that allele is within the population .How many as well as in whole population.

10. The Hardy Weinberg Equilibrium Equation p 2 + 2pq + q 2 = 1 (p = the frequency or percentage of the dominant allele in decimal format, q = the frequency or percentage of the recessive allele in decimal format) Since p is the frequency of all dominant alleles (A), it counts all of the homozygous dominant individuals (AA) and half of the heterozygous individuals ( Aa ). Likewise, since q is the frequency of all recessive alleles (a), it counts all of the homozygous recessive individuals ( aa ) and half of the heterozygous individuals ( Aa ).

11. Therefore, p 2 stands for all homozygous dominant individuals, q 2 stands for all homozygous recessive individuals, and 2pq is all heterozygous individuals in a population. Everything is set equal to 1 because all individuals in a population equals 100%. This equation can accurately determine whether or not evolution has occurred between generations and in which direction the population is heading.

12. population: 100 cats 84 black, 16 white How many of each genotype? q 2 (bb): 16/100 = .16 q (b): √.16 = 0.4 p (B): 1 - 0.4 = 0.6

13. Using Hardy-Weinberg equation bb Bb BB p 2 =.36 2pq =.48 q 2 =.16

14. Assumptions of Hardy-Weinberg equilibrium 1 . Mating is random 2. Population size is infinite (i.e., no genetic drift) 3. No migration 4. No mutation

15. REFERENCES:- Genetics A.V.S.S. SAMBAMURTY Genetics BENJAMIN A. PIERCE