Reassessment of genetic diversity in native turkish sheep breeds with large numbers of microsatellite markers and mitochondrial DNA (MTDNA)


Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Fen Edebiyat Fakültesi, Biyolojik Bilimler Bölümü, Türkiye

Tezin Onay Tarihi: 2009

Öğrenci: ŞÜKRÜ ANIL DOĞAN

Danışman: İNCİ ZEHRA TOGAN

Özet:

In the present study, within and among breed genetic variability in seven native Turkish sheep breeds (Akkaraman, Dağlıç, Gökçeada, İvesi, Karayaka, Kıvırcık and Morkaraman) were analyzed based on 20 microsatellite loci. For the analysis, various statistical methods such as Neighbor-Net, Factorial Correspondence Analysis (FCA) and Structure were used. High level of genetic variability within the Turkish breeds was observed. Gene pools of the breeds were visualized and found that they are highly overlapping with each other. As one of the reasons of this overlap, genetic exchange between the breeds was suggested. Dağlıç, claimed to be the ancestors of first domestic sheep in Anatolia, seemed to be the most admixed one. Yet Dağlıç, despite being the most introgressed one, still might be exhibiting its uniqueness. Observations implied that conservation practices concerning Dağlıç must be urgently revised. Results of the present study do not support previous observations about the genetic differentiation patterns of the breeds within Anatolia. Possible reasons of the discrepancies between the observations were discussed. Genetically extreme individuals can be identified by Structure, Assignment and FCA tests. These methods are found to be promising in establishing new relatively pure breeds or in saving the breeds from further genetic contamination. Genetically outlier individuals were shown not to exhibit any distinct morphological differences. Unknown band patterns were found by RFLP and SSCP of mtDNA Control Region and the individuals harboring those were sequenced. They were shown to belong to the common haplogroups A, B or C. No novel haplogroup was found.