Project 1
Frog Gels: Analysis of Skin
John Donich
Claudia Morales
Kevin Berry
Project description
 Goal: to describe the set of proteins in 7.5%
gels and 12 % gels…
 Are males differentiable from females…?
 Are individuals differentiable?
An ideal model…
 There is little variation between frogs of the
same sex
 There’s a distinct diference in the set
between sexes
 A protein that shows in only one of the
sexes
Method
 Measured relative mobility of protien bands
 Plotted standards’ relative mobility vs. Log
Molecular Weight
 Chose a model and fit the data
 Looked for patterns within individuals and
between sexes
Choosing models
 Linear Model for 7.5% gels…


Only 3 Degrees of Freedom (5 Standards)
Linear Model had smallest confidence interval
 Cubic Model for 12% gels…


5 Degrees of Freedom (7 Standards)
Cubic and Linear models had similar
confidence intervals, but R2-adj better for cubic
(99% vs 96%)
Linear Model
5.4000
y = -0.8192x + 5.4079
R2 = 0.9754
5.3000
5.2000
Log Molecular Weight
5.1000
5.0000
4.9000
4.8000
4.7000
4.6000
4.5000
0.0000
0.2000
0.4000
0.6000
Relative Mobility
0.8000
1.0000
1.2000
Cubic Model
5.4000
3
2
y = -1.838x + 3.8188x - 3.1736x + 5.4975
R2 = 0.999
5.2000
Log molecular Weight
5.0000
4.8000
4.6000
4.4000
4.2000
0.0000
0.1000
0.2000
0.3000
0.4000
0.5000
relative mobility
0.6000
0.7000
0.8000
0.9000
1.0000
Conclusions
 The variation among individuals is present
 The sex of a frog cannot be determined by
protein gel analysis
 There is no single protein that distinguishes
sexes
?