This evening my wife tried to start a load of towels in the dryer and it would not turn on. The light comes on when you open the door, initially I thought it might be a power/door switch problem, its not. I took the control panel off to expose the switches. I checked the switches individually with a volt meter and I’m getting power to the timer switch but there seems to be no power to the start switch. I am not sure how the start switch works on a dryer but was thinking that there should be readable power to it. Without taking the whole dryer apart panel by panel, would it make sense that the start switch is bad or should I be looking somewhere else for the problem. Thanks. 
there are different heat sensors that have to have continuity before power can be sent to the start button. If you have a schematic diagram look to see what all contacts need to be continous to get power to the start. If you don’t understand what I am saying ask any good union electrician. All devices that deal with safety in line with the start must have continuity.
Your model number seems to be missing a few digits though all units in this series are probably close.
I used DS4500EA0WW
Replacement parts for DS4500 models | AppliancePartsPros.com
I do not have a wiring diagram for this unit.
GE likes to keep all tech data a secret.
High on the list would be the thermal fuse (Item 507 in Section 4).
If this is blown check/clean your vent system as this is often the cause of it blowing.
If it is blown you have to find out what caused it to go.
Note: that sometimes they do just blow on their own but changing it without checking other things is a gamble.
Check the heating coils.
Unplug the unit and both wires to the coil.
Check it with a meter, should be around 12 ohms.
Then check from each side of the coil to the case/frame, both should be infinite ohms (open). If not the coil may have sagged or broken and is touching the case. This can cause it to run on high and the thermostats cannot regulate it.
If the above is OK then you will also have to replace the hi-limit as it should have regulated the temperature so the fuse did not blow.
You still have to find out why it blew.
Check that the belt is OK.
Check the seals (drum etc) in the unit. The air is pulled over the heating coils, through the drum and pushed out the exhaust. So any large seal leak will pull in room air and the cycling thermostat on the blower will run the unit hot.
Check that the lint filter is not coated with fabric softener residue which greatly reduces air flow.
Check/clean your vent system.
Check/clean the blower wheel.
If all OK you may want to replace the cycling thermostat as it’s contacts may not be opening (welded shut).
May also be the belt switch, depending on how it is wired in.
Here is a good link with info on GE dryers.
http://www.applianceaid.com/ge-dryers.html
Check out #28 sample Wiring Diagrams
I think yours is probably close to #4 Newer GE’s.