Can you extract DNA and RNA at the same time?

It is often useful to be able to isolate both RNA and DNA from the same biological specimen, especially when the sample is in short supply or when different manipulations are contemplated (for example, genomic PCR and RT-PCR).

How do you extract DNA and RNA?

DNA and RNA can also be isolated from the same biological sample by extracting a total nucleic acid fraction and dividing it into two parts – one of which will be treated with a DNase 1 while the other portion will be treated with RNase A to recover RNA and DNA, respectively.

Can DNA quality from FFPE tissues still be improved given that they have been stored for years?

FFPE tissues are often used in retrospective studies although they suffer from notable DNA and RNA degradation. In the present study, we found that long-term storage of FFPE tissues increased the level of DNA and RNA degradation and reduced the quantity of DNA and RNA extracted.

What is FFPE DNA extraction?

Formalin-fixed paraffin-embedded (FFPE) tissues are a very common source of archived tissue samples that have been used by pathologists for decades. It allows for a long-term, room temperature storage solution for tissue samples, making it very convenient.

What are the main differences between DNA extraction versus RNA extraction?

The main difference between DNA and RNA extraction is that the pH level of DNA extraction is pH 8 whereas the pH level of RNA extraction is pH 4.7. DNA tends to denature and move to the organic phase at acidic pH.

Is DNA extraction same as RNA extraction?

The main difference between DNA and RNA extraction is that the pH level of DNA extraction is pH 8 whereas the pH level of RNA extraction is pH 4.7. DNA and RNA extraction are the two procedures involved in the isolation and purification of nucleic acids from the cells of tissues. Both procedures consist of three steps.

Why do we extract RNA instead of DNA?

The cells in our bodies become structurally and functionally diverse by activating different combinations of genes. In short, examining DNA provides us with a static picture of what a cell or organism might do or become, whereas measuring RNA lets us see what a cell/organism is actually doing right now.

How do you improve DNA quality FFPE?

Conclusion. The best DNA quality ratio of FFPE to frozen tissue DNA is obtained by fixation with 10\% neutral formalin for 1 day and heat treatment of tissue lysates at 95°C for 30 minutes.

How do you store blocks in FFPE?

Formalin-fixed paraffin-embedded (FFPE) tissue can also be stored above freezing. If the samples will only be used for histology in the future, they can be stored indefinitely at room temperature. However, if you intend to extract DNA or RNA from the samples, it’s much better to store them at 4°C.

How is DNA extracted from paraffin embedded tissue?

To extract DNA from paraffin-embedded samples, tissue cores or microdissected tissue are subjected to xylene treatment, which dissolves the paraffin from the tissue, and then rehydrated using a series of ethanol washes. Proteins and harmful enzymes such as nucleases are subsequently digested by proteinase K.

How do you Deparaffinize a slide?

Before deparaffinization, place the slides in a 55°C oven for ten minutes to melt the paraffin. Deparaffinize slides in 2 changes of xylene or xylene substitute for 5 minutes each. Transfer slides to 100\% alcohol, 2 changes for 3 minutes each and transfer once through 95\% alcohol for 3 minutes.

What is the quality of RNA extracted from colonic biopsies?

RNA quality assessment. These plots and electropherogram show 12 RNA preparations extracted from fresh human colonic biopsies. The quality of these preparations, as judged by the absence of any bands other than the 28S, 18S, and 5S rRNA, is very high.

How much DNA contamination is visible on Bioanalyzer RNA-chips?

On Bioanalyzer RNA-chips, DNA contamination will be visible in the size range 4 kb to 10 kb. If you are using a Trizol protocol for the RNA extractions we would highly recommend cleaning the samples afterwards with a spin column kit (e.g. RNA-clean & concentrator kits) to remove any phenol traces.

How can I remove RNase I from my DNA samples?

For the removal of RNase I, Ampure XP beads (or similar) or DNA-clean & concentrator kits will work fine (we suggest extending incubation times for elutions from the columns to at least 5 minutes or to perform two elutions). DNA samples can be QC-ed easily by agarose gel electrophoresis and ethidium bromide staining.

What is the best way to isolate RNA without DNA?

RNA samples need to be DNA-free. The RNA isolation protocol should always include a DNase digestion step; in problematic cases use RNA-clean & concentrator kits with DNase. On an agarose gel, DNA contamination will be visible as a smear or band of fragments considerably larger than the RNA (>10 kb).