Varijabilnost mitohondrijske DNA goveda

master's thesis

• Title (english): Variability of cattle mitochondrial DNA
• Author: Ivana Duvnjak
• Mentor: Vlatka Čubrić Čurik (mentor)
• Committee member: Vlatka Čubrić Čurik (predsjednik povjerenstva)
• Committee member: Maja Ferenčaković (član povjerenstva)
• Committee member: Ino Čurik (član povjerenstva)
• Committee member: Vladimir Brajković (član povjerenstva)
• Granter: University of Zagreb; Faculty of Agriculture; (Department of Animal Science I); Zagreb
• Defense date and country: 2017-07-10, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Agronomy; Genetics and Breeding of Plants, Animals and Microorganisms

Abstract

Uloga divljeg tura (B. primigenius) tijekom domestikacijskih procesa te utjecaj na formiranje
domesticiranih i modernih pasmina goveda (B. taurus) nije do kraja razjašnjena. Postoje
teorije prema kojima sve moderne pasmine goveda imaju jedinstveno podrijetlo s Bliskog
istoka i nastale su domestikacijom populacije divljeg tura s tog područja te teorije prema
kojima su one nastale tijekom više nezavisnih lokalnih domestikacijskih procesa uz
introgresiju divljeg tura te uz dotok gena sjevernoafričkih goveda u područje južne Europe.
Cilj ovog rada je rekonstrukcijom distribucije varijabilnosti mtDNA modernih pasmina i
arheo-uzoraka u prostoru i vremenu dodatno razjasniti utjecaj divljeg tura na formiranje
modernih pasmina. U analizi je korišteno ukupno 635 nukleotidnih sljedova kontrolne regije
mtDNA duljine 237 bp iz NCBI baze podataka te iz uzoraka prikupljenih i analiziranih u
ovom radu. Analiza i obrada nukleotidnih sljedova odrađena je putem programa MEGA7,
DNasp5 i Mitotoolpy, a vizualizacija distribucije varijabilnosti i filogenetskih odnosa putem
MJ mreže u PopArtu. Rezultati su pokazali veliku varijabilnost mtDNA kod goveda te porast
varijabilnosti kroz vrijeme. Analizom haplogrupa utvrđeno je postojanje svih glavnih
haplogrupa u odabranim uzorcima te su određene nepoznate haplogrupe za odabrane arheouzorke.
Potvrđen je i utjecaj gena iz područja sjeverne Afrike na formiranje južnoeuropskih
modernih pasmina goveda. Analizom geografske rasprostranjenosti utvrđene su tri moguće
lokacije nezavisne domestikacije iz kojih su domesticirana goveda mogla migrirati. Tijekom
migracije moglo je doći do introgresije lokalnih populacija divljeg tura. Za preciznije i točnije
određivanje filogeneze modernih pasmina goveda i tijek domestikacije potrebno je u analize
uključiti druge regije mtDNA, različite utjecaje kojima su one podložne (npr. selekciji),
utjecaj molekularnog sata, datiranje arheo-uzoraka te koristiti dostupne nove tehnologije.

Abstract (english)

The role of the aurochs (B. primigenius) during domestication and it's impact on the formation
of modern cattle breeds (B. taurus) is not entirely clarified. There are two oposite theories.
According to first one, all modern cattle breeds have a unique origin from the Middle East and
were created by domestication of the wild local population of aurochs. According to the other,
modern cattle breeds have multiple origin with genetic contribution of European aurochsen
and gene flow from North Africa to Southern Europe. The aim of this paper is to resconstruct
the variability distribution of mtDNA from modern and ancient cattle trough space and time
to further clarify the impact of aurochs on the formation of modern breeds. The analysis
included total 635 sequences of mtDNA control region, 237 bp long, from modern and
ancient samples from the NCBI database and own resources. Analysis of sequences was
performed using MEGA7, DNasp5 and Mitotoolpy. Vizualization of variability distribution
and phylogenetic relationships was performed via MJ network in PopArt. The results showed
high variability of mtDNA in cattle and increased variability over time. The analysis of
haplogroups revealed the existence of all major haplogroups in the selected samples set. The
unknown haplogroups of ancient samples were determined. The influence of North African
genes on the formation of South European cattle breeds was confirmed. By analyzing
geographical distribution, at least three possible locations of independent domestication were
identified. From these locations domesticated cattle could migrate to the other locations and
durig the migration the introgression of local aurochsen could occur. For more precise and
accurate determination of the phylogeny of modern cattle breeds and revealing domestiction
events, it is necessary to include other regions of mtDNA. Different influences (eg. selection)
on each region should also be included. The influence of molecular clock and radiometrical
dating of ancient samples should be performed in anaysis of samples with large time span.
Also the use of available new technologies would be recommended.

• Keywords: domestikacija goveda; kontrolna regija mtDNA; varijabilnost; MJ mreža; haplogrupe
• Keywords (english): cattle domestication; mtDNA control region; variability; MJ network; haplogroups
• Language: croatian
• URN:NBN: urn:nbn:hr:204:936722
• Study programme: Title: Animal Genetics and Breeding; Study programme type: university; Study level: graduate; Academic / professional title: magistar/ magistra inženjer/inženjerka genetike i oplemenjivanja životinja (magistar/ magistra inženjer/inženjerka genetike i oplemenjivanja životinja)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Repository: Repository Faculty of Agriculture University of Zagreb
• Created on: 2017-07-25 12:36:35