Hasan Meydan

SCREENING FOR BOVINE LEUKOCYTE ADHESION DEFICIENCY, DEFICIENCY OF URIDINE MONOPHOSPHATE SYNTHASE, COMPLEX VERTEBRAL MALFORMATION, BOVINE CITRULLINAEMIA, AND FACTOR XI DEFICIENCY IN HOLSTEIN COWS REARED IN TURKEY

BackgroundBovine leukocyte adhesion deficiency (BLAD), deficiency of uridine monophosphate synthase (DUMPS), complex vertebral malformation (CVM), bovine citrullinaemia (BC) and factor XI deficiency (FXID) are autosomal recessive hereditary disorders, which have had significant economic impact on dairy cattle breeding worldwide. In this study, 350 Holstein cows reared in Turkey were screened for BLAD, DUMPS, CVM, BC and FXID genotypes to obtain an indication on the importance of these defects in Turkish Holsteins.MethodsGenomic DNA was obtained from blood and the amplicons of BLAD, DUMPS, CVM, BC and FXID were obtained by using PCR. PCR products were digested with Taq I, Ava I and Ava II restriction enzymes for BLAD, DUMPS, and BC, respectively. These digested products and PCR product of FXID were analyzed by agarose gel electrophoresis stained with ethidium bromide. CVM genotypes were detected by DNA sequencing. Additionally, all genotypes were confirmed by DNA sequencing to determine whether there was a mutant allele or not.ResultsFourteen BLAD, twelve CVM and four FXID carriers were found among the 350 Holstein cows examined, while carriers of DUMPS and BC were not detected. The mutant allele frequencies were calculated as 0.02, 0.017, and 0.006 for BLAD, CVM and FXID, respectively with corresponding carrier prevalence of 4.0% (BLAD), 3.4% (CVM) and 1.2% (FXID).ConclusionThis study demonstrates that carriers of BLAD, CVM and FXID are present in the Turkish Holstein population, although at a low frequency. The actual number of clinical cases is unknown, but sporadic cases may appear. As artificial insemination is widely used in dairy cattle breeding, carriers of BLAD, CVM and FXID are likely present within the population of breeding sires. It is recommended to screen breeding sires for these defective genes in order to avoid an unwanted spread within the population.

Identification of factor XI deficiency in Holstein cattle in Turkey

BackgroundFactor XI (FXI) is a plasma protein that participates in the formation of blood clots. Factor XI deficiency is autosomal recessive hereditary disorder that may be associated with excess bleeding in Holstein cattle.MethodsIn this study, 225 Holstein cows reared in Turkey were screened in order to identify FXI genotypes. DNA extractions were obtained from the fresh blood of the cows. Amplicons of FXI exon 12 were obtained by Polymerase Chain Reaction (PCR), and analyzed by 2% agarose gel electrophoresis stained with ethidium bromide. Additionally, all cows were confirmed by DNA sequencing to determine whether or not there was a mutant allele.ResultsCarriers of the FXI deficiency have two DNA fragments of 320 bp and 244 bp in size. The results of our study demonstrated that only four out of the 225 Holstein cows tested in Turkey carried the FXI deficiency. The frequency of the mutant FXI allele and the prevalence of heterozygous cows were found as 0.9% and 1.8%, respectively.ConclusionThe DNA-based test determines all genotypes, regardless of phenotype or FXI activity. The mutation responsible for the FXI deficiency had not been detected in Holstein cattle in Turkey before prior to this study. The frequency of the mutant FXI allele needs to be confirmed by carrying out further analyses on cattle in Turkey and the selection programs should be developed to eliminate this genetic disorder.

Novel polymorphisms in ovine prion protein gene

The aim of this study was to identify the PRNP polymorphisms outside the standard codons 136, 154 and 171 in 1110 sheep with no clinical sign of scrapie from all 18 Turkish native sheep breeds and compare our results with published data on ovine PRNP polymorphism from other regions of the world. Among the 22 amino acid polymorphisms and three silent mutations, 10 were novel for ovine PRNP: p.Gly94Gly, p.Leu128Ile, p.Met132Leu, p.Ser135Arg, p.Met137Val, p.Asn146Lys, p.Arg159Arg, p.Tyr160Asn, p.Gln163His and p.Thr193Ser. These data reveal that sheep breeds close to the historic center of small ruminant domestication have remained highly diverse in the prion gene locus, with distinctive genetic similarities to both Asian and European sheep breeds.

Prion protein gene polymorphism and genetic risk evaluation for scrapie in all Turkish native sheep breeds

The aim of this study was to identify the prion protein (PrP) gene polymorphism in a total of 1,110 healthy sheep from 18 Turkish native sheep breeds. There were nine alleles and 22 genotypes observed based on codons 136, 154, and 171 of the PrP gene. The ARQ allele was predominant for all breeds. The most resistant allele to scrapie, ARR, was present in all breeds. The VRQ allele, associated with the highest susceptibility to scrapie, was detected at low frequencies in İvesi (0.06), Kıvırcık (0.021), Sakız (0.010), Karayaka (0.011), Çine Çaparı (0.012), and Güneykaraman (0.017). In general, the ARQ/ARQ genotype was predominant in all breeds. The most resistant genotype to scrapie, ARR/ARR, was found with the frequency lower than 0.180. The most susceptible genotype, VRQ/VRQ, was found in only Kıvırcık. The TRR and TRH alleles and the genotypes of ARR/TRR, ARR/ARK, and ARH/TRH have been found for the first time in Turkish native sheep breeds. According to these results, all breeds belong to risk group R3 followed by R2. It is propounded that the susceptibility to scrapie increased from eastern to western part of Turkey. Our findings of Turkish native sheep breeds with PrP gene polymorphisms will assist the sheep breeding program for selection of scrapie resistance genotypes to reduce the risk of scrapie.

Mitochondrial DNA Variation in the CoxI–CoxII Intergenic Region among Turkish and Iranian Honey Bees (Apis mellifera L.)

The western honey bee, Apis mellifera L., is native to Africa, the Near and Middle East, and Europe. Based on morphometrics, the Near Eastern subspecies, Anatolian (A. m. anatoliaca), Caucasian (A. m. caucasica), and Iranian (A. m. meda), were grouped within the Middle Eastern O branch (Ruttner 1988; Kauhausen-Keller et al. 1997); however, mtDNA analysis has shown that they belong to the East Mediterranean C lineage (Smith et al. 1997; Palmer et al. 2000; Franck et al. 2000, 2001; Kandemir et al. 2006; Ozdil et al. 2009). According to Ruttner’s (1988) morphometric analysis, A. m. anatoliaca occupies nearly all of Turkey, A. m. caucasica is found in the northeastern part of Turkey, and A. m. meda is found primarily in Iran but also in the southeastern part of Turkey. Length and restriction site polymorphisms within the CoxI–CoxII intergenic region of the honey bee mitochondrial genome have been particularly useful in differentiating evolutionary lineages and groups of subspecies (Cornuet and Garnery 1991; Hall and Smith 1991; Garnery et al. 1992, 1993; Franck et al. 2000, 2001; Palmer et al. 2000). For example, DraI restriction of this region revealed more than 50 haplotypes in lineages A and M (Garnery et al. 1992, 1993; Franck et al. 2000, 2001) but only six haplotypes in lineage C (Franck et al. 2000; Kandemir et al. 2006; Ozdil et al. 2009), including one discovered recently (Ozdil et al. 2009).