Dear Samsher

• it might be difficult to visualise cDNA on an agarose gel in any meaningful way 
• it is definitely possible to visualise RNA amplified FROM cDNA on a gel and this appears as a smear between your 2 dominant rRNA ribosomal subunits
• However cDNA itself might be indistinguishable qualitatively  from low grade total RNA especially if that RNA is degraded and manifests as a smear and also if contaminated with genomic DNA which can also manifest as a smear
• Quantitatively as already mentioned there might also be a problem with visualisation on a standard agarose gel
• When gave visualised amplified RNA derived from cDNA in the past this has been carried out on Agilent bio chips NOT agarose gels; these chips are more sensitive 
• I guess what is pertinent is to ask why you would wish to visualise your cDNA
• In terms of cDNA quality and efficiency of synthesis this is normally evaluated by making sure your starting RNA has a 260/280 ratio of 1.8 to 2.2 - implying low protein contamination - and a 260/230 ratio of > 1.0 implying negligible contamination with phenol or trizol if RNA extracted manually and/or negligible contamination with guanidinium salts (added to trizol and kit lysis buffers which are designed to inhibit proteases and RNAses and, if they bleed through into your final RNA prep will also inhibit RT leading to poor cDNA synthesis)
• Once the RNA quality has been checked by nanodrop or fluorimetry this way you can then run 1ug of your RNA either on an agarose gel or on a Nanodrop to check for lack of degradation which nano drop alone will not tell you about
• In this case for mammalian total RNA you will see 2 x dominant rRNA species if your RNA us undegraded or a smear if your RNA is degraded
• If undegraded you then take 1ug of your RNA , perform RT and normally validate the quality of your cDNA by PCR amplification of 1ul of your 20-100ul of cDNA total volume by PCR using primers to a high copy number housekeeping gene like gapdh or b actin 
• Incidentally you mentioned that your measure your cDNA yield: This is valid providing you either measure by fluorimetry Sybr type dyes ( e.g the qubit system) which just bind to nucleic acids or nano drop in the case of column or purified or ethanol precipitated cDNA 
• ( I do not recommend ethanol ppt for quantitative qPCR by the way as it will bias your cDNA population; for simple presence or absence of gene it is acceptable) 
• what you CANNOT do is simply meadure your cDNA by nanodrop or spectrophotometer at 260nM without purification as measurement will not be specific to cDNA and much of your reading will be unincorporated dNTPs ( left over from cDNA synthesis) and residual genomic DNA ( present in parent RNA preparation) 

from my own experience, the DNA band should reach 20 ng to be visualized on agarose gel. If your cDNA was prepared from total RNA and without PCR amplification, the cDNA amount may be less than 20 ng and would look like a smear, ranging from several bp to several kilo-bp, thus below the detection limit of the imaging system. To check the quality of freshly prepared cDNA on gel, I guess you have to concentrate multiple reaction products and run in the single lane. In addition, dilute the DNA ladder in 1:10, and run in parallel with the cDNA lane.

Dear Samsher

• it might be difficult to visualise cDNA on an agarose gel in any meaningful way 
• it is definitely possible to visualise RNA amplified FROM cDNA on a gel and this appears as a smear between your 2 dominant rRNA ribosomal subunits
• However cDNA itself might be indistinguishable qualitatively  from low grade total RNA especially if that RNA is degraded and manifests as a smear and also if contaminated with genomic DNA which can also manifest as a smear
• Quantitatively as already mentioned there might also be a problem with visualisation on a standard agarose gel
• When gave visualised amplified RNA derived from cDNA in the past this has been carried out on Agilent bio chips NOT agarose gels; these chips are more sensitive 
• I guess what is pertinent is to ask why you would wish to visualise your cDNA
• In terms of cDNA quality and efficiency of synthesis this is normally evaluated by making sure your starting RNA has a 260/280 ratio of 1.8 to 2.2 - implying low protein contamination - and a 260/230 ratio of > 1.0 implying negligible contamination with phenol or trizol if RNA extracted manually and/or negligible contamination with guanidinium salts (added to trizol and kit lysis buffers which are designed to inhibit proteases and RNAses and, if they bleed through into your final RNA prep will also inhibit RT leading to poor cDNA synthesis)
• Once the RNA quality has been checked by nanodrop or fluorimetry this way you can then run 1ug of your RNA either on an agarose gel or on a Nanodrop to check for lack of degradation which nano drop alone will not tell you about
• In this case for mammalian total RNA you will see 2 x dominant rRNA species if your RNA us undegraded or a smear if your RNA is degraded
• If undegraded you then take 1ug of your RNA , perform RT and normally validate the quality of your cDNA by PCR amplification of 1ul of your 20-100ul of cDNA total volume by PCR using primers to a high copy number housekeeping gene like gapdh or b actin 
• Incidentally you mentioned that your measure your cDNA yield: This is valid providing you either measure by fluorimetry Sybr type dyes ( e.g the qubit system) which just bind to nucleic acids or nano drop in the case of column or purified or ethanol precipitated cDNA 
• ( I do not recommend ethanol ppt for quantitative qPCR by the way as it will bias your cDNA population; for simple presence or absence of gene it is acceptable) 
• what you CANNOT do is simply meadure your cDNA by nanodrop or spectrophotometer at 260nM without purification as measurement will not be specific to cDNA and much of your reading will be unincorporated dNTPs ( left over from cDNA synthesis) and residual genomic DNA ( present in parent RNA preparation) 

In my answer above i meant to say check that your RNA is undegraded either by running on an 0.8% agarose gel or Agilent biochip NOT nanodrop as stated above. This was a typo I wasn't able to correct ! 

My answer would be yes you can visualize cDNA on a 0.8-1% agarose gel, but one wont find specific bands. From my personal experience if you run just 2-3 microliters of the undiluted cDNA you can find a sheared band between 700-800bp. I had tried running a diluted sample but couldn't find the same. 

Hope this helps!!

Really you right

good jop