FAQs: MolecuLab 217/218
Q: Why must I rehydrate the DNA samples I received?
DNA samples are dehydrated for stability during long-term storage. You can give your students extra practice with pipetting by having them rehydrate the samples shortly (within 1 week) before their use. Alternatively, you can save your precious class time by rehydrating the samples yourself or by having a teaching assistant/student worker rehydrate the samples for you.
Q: What are the band sizes of the DNA Ladder?
The DNA ladder is a 100bp ladder. The largest band is 2072bp. The second largest band is 1500bp and each band thereafter is 100bp smaller.
- See the following figure for the band sizes.
Q: Do the band patterns reflect heterozygous and homozygous conditions?
The specific form of porphyria being tested for is PCT, a heterozygous condition. Thus, the band patterns revealed by electrophoresis are RFLP patterns that are testing for the presence of particular mutations within the UROD gene. A band pattern that matches the pattern of the Proband (diagnosed individual) within the same group suggests that that individual has the same mutations as the Proband and that a PCT diagnosis is likely. The patterns should not be analyzed for and are not meant to reflect homozygous and heterozygous conditions.
Q: How many microliters of 1X loading dye do I need to add to my dried down DNA samples in MolecuLabs 217/218?
Add 12µL of 1X loading dye to rehydrate each sample.