A simple and efficient method for extraction of PCR-amplifiable DNA from chicken eggshells

ABSTRACT Recently, we reported a method for discriminating a Japanese brand of chicken, the Hinai‐jidori. As an application of this method for discriminating Hinai‐jidori eggs, we here report an efficient method for extracting maternal DNA from eggshells. Eggshell powder was completely decalcified with EDTA solution, and then DNA was isolated by conventional phenol‐chloroform extraction and ethanol precipitation. The efficiency of DNA recovery from eggshells was 50‐fold higher than that of a previously reported method. The recovered DNA could be used for PCR, and 10 markers for identifying the Hinai‐jidori chicken were detected. The genotypes of the Hinai‐jidori exactly matched those of the Hinai‐dori breed. Using this method, Hinai‐jidori and Hinai‐dori eggs could be distinguished from the eggs of Rhode Island Reds. This is the first report of a technique that can be used to discriminate the eggs of Hinai‐jidori from those of other chickens, and it can also be utilized to validate the labeling of Hinai‐jidori eggs in the market.