Abstract. In this study, the κ-casein (CSN3) and lactoferrin
(LTF) genes which were found in association with milk production
traits in different animal species were studied firstly in Turkish donkey
populations. A total of 108 donkeys from different regions of Turkey were
used in order to reveal the different genotypes of CSN3 and
LTF genes by using polymerase chain reaction – restriction fragment
length polymorphism (PCR-RFLP) and DNA sequencing methods. To determine the
genetic polymorphism, we attempted to digest a fragment of 235 bp of the
CSN3 gene and a fragment of 751 bp of the LTF gene using
PstI, and DraII, EagI and MboI
restriction enzymes, respectively. Neither the CSN3 gene nor the
LTF gene had enzyme recognition sites with the PstI,
DraII and MboI restriction enzymes in all of the studied
samples. However, the LTF gene was only distinguished with the
EagI restriction enzyme. Three genotypes were identified in the
LTF gene with the EagI restriction enzyme: GG homozygotes
(667, 84 bp), AG heterozygotes (751; 667, 84 bp) and AA homozygotes
(751 bp). The transition from guanine to adenine in 89 bp of the
LTF gene lacks the restriction site and different genotypes are
obtained. This novel single nucleotide polymorphism (SNP) has been firstly
detected in donkeys. According to the results, the G allele was predominant
in the LTF-EagI gene in the studied Turkish donkey populations. In
this study, all the genotype distributions of LTF-EagI were not
found in Hardy–Weinberg equilibrium (P<0.05). The CSN3
and LTF genes have not been studied before in donkeys, so the
results are the preliminary results of these gene regions in donkeys.
Designing Randomized DNA Sequences Free of Restriction Enzyme Recognition Sites
