MATHEMATICS PROJECT
DNA melting temperature and calculation of allele frequency
AIM: To find the temperature at which DNA denatures and in calculating allele
frequency.
PRINCIPLE: To find the melting temperature using linear functions and represent
graphically and to find allele frequency using power functions a.
SUMMARY: DNA is a double helix held together by hydrogen bonds between
base pairs. There are four base pairs namely Adenine (A), Guanine (G),
Cytosine(C) and Thymine (T). Adenine always pairs with Thymine and Guanine
always pairs with Cytosine. There are 2 hydrogen bonds between A and T and 3
hydrogen bonds between G and C. The 2 strands separate when the DNA is
denatured. Denaturation is a process by which double stranded DNA unwinds
and separates. During denaturing, the energy required to break hydrogen bonds
between G and C is more than that of A and T. It is because of the reason that
there are more number of hydrogen bonds between G and C compared to A and
C. To find out the temperature at which DNA denatures we make use of linear
equations.
Linear equation is an equation which consists of a single variable
whose degree is one and is a constant. The linear equation used is:
Tm =81.5 +16.6(log [Na+ ]) +0.41(%GC) – (500/length of DNA)
There is a linear graph which shows relationship between TM and percent of
GC content. Denaturing of DNA result in mutation which can be positive,
negative or lethal. Hardy Weinberg law is used to show what happens to alleles
and genotypes in an ideal population (Allele is a contrasting pair in a gene).
According to the law the distribution of genotypes among the zygotes is
P2+2pq+q2=1
A power function is a function of the form f(x) = axp where a is not equal to 0 is a
constant and p is a real number.
Allele frequency is a measure of a relative frequency of an allele on a genetic
locus in a population. They show the genetic diversity of a species. The
equilibrium frequency of an allele a is given by
q=õ/s
Where 0<s<1 and s is selection coefficient and µ is the mutation which occurs in
forward direction.
PARTICIPANT DETAILS
1) RACHANA – 9886810145
2) SUPRIYA M – 9008617977
3) APPORVA N – 9035507629
Institution and faculty details:
Name: Mrs. ANITHA K V
Designation: LECTURER IN MATHEMATICS
Contact Number: 8050246873
Email id: anitha.kv@cjc.christcollege.edu
Institution’s postal address:
CHRIST JUNIOR COLLEGE
HOSUR ROAD
BANGALORE
Institution contact number: (080)40129292