Modified phenol chloroform protocol for genomic DNA extraction from keratinous tissue

DNA extraction enables the isolation and purification of genetic material by physical-chemical methods. There are specific protocols for different types of samples as animal and plant tissue. However, there are variations and particularities according to the nature of the fabric, such as the high presence of keratin. Thus, the present work aimed to develop and optimize a DNA extraction protocol from feather based on the Phenol-Chloroform method. Feather samples werw collected from 9 birds native to the Amazon region for the genetic material extraction. The DNA was precipitated with isopropanol and washed with 70% ethanol. Subsequently, the pellet was disolved in the TE buffer. The results indicated satisfactory concentrations for post-extraction molecular biology techniques such as PCR. The protocol showed a significant reduction in the incubation time to 1 hour compared to other protocols aimed at feather samples. Addition proteinase K to the lysis solution was the main factor that led to the optimization of the extraction time. The A260/230 and A260/280 absorbance ratios indicated the quality of the extracted DNA being close to what expected. Therefore, the results demonstrate the potential protocol use for molecular biology studies in birds from feather samples. However volume of phenol-chloroform and 70% ethanol can still be adjusted to suit the type sample.