Antik İnsan Kemik ve Diş Örneklerinde DNA İzolasyon Metotlarının Verimlilik Açısından Karşılaştırılması
Özet
Ancient DNA refers to DNA in severely damaged materials such as teeth and bones that come from museum specimens or excavations. The study of ancient DNA has made it possible to read the genetic sequences of extinct organisms, clarify kinship relationships, reveal the evolutionary origins of human populations, and preserve the sequences of ancient pathogens. With the development of PCR technology, the study of ancient DNA has evolved, but the sensitivity and susceptibility of this technology to contamination has also led to problems in this area. Damage to ancient DNA makes it difficult to extract DNA from materials such as bones and teeth and severely limits the length of DNA that can be recovered. Although studies of ancient DNA are diverse, isolation of DNA and improvement of PCR success have been important topics in the field since their first appearance. Successful isolation of DNA from the sample is a prerequisite for reading the sequences of ancient samples and for other molecular determinations. For this purpose, two methods are usually used to isolate ancient DNA: phenol-chloroform and silica membrane isolation.
The aim of this work is to compare the silica membrane and phenol-chloroform isolation methods in terms of efficiency and amplifiable DNA lengths. For the amplification of mitochondrial DNA, 3 different primer pairs were used, yielding products in sizes of 162 bp, 177 bp and 218 bp. In this context, silica membrane and phenol-chloroform isolations were performed on 5 femur, 5 talus, and 5 tooth samples in the studies, and the success of these methods on different sample types was compared. The samples were obtained from the excavations of Stratonikeia Ancient City located in the Caria Region.
The experiments showed that only the shortest amplicon (162 bp) was successful in phenol-chloroform isolation of femur and talus specimens. Isolation of the same specimens with silica membranes yielded successful results for all three amplicons. Thus, the isolation method with silica membranes was shown to be more successful than the isolation method with phenol-chloroform samples for femur and talus samples, both in terms of efficiency and amplifiable length. For dental samples, the phenol-chloroform method yielded dense bands with the shortest amplicon length, whereas the silica membrane method yielded less dense but longer amplicon lengths. Although the method used may vary depending on the type of sample, silica membrane isolation was found to be more successful compared to phenol-chloroform isolation.
