Aylin Köseler

High Incidence of Hb D-Los Angeles [β121(GH4)Glu→Gln] in Denizli Province, Aegean Region of Turkey

Denizli Province is located in the inner part of the Aegean region of Turkey and is one of the target areas for premarital screening. Here we report the abnormal hemoglobins (Hbs) observed during a premarital screening program in our region. According to our results, Hb D-Los Angeles [β121(GH4)Glu→Gln (GAA→CAA] (also known as D-Punjab, D-North Carolina, D-Portugal, Oak Ridge and D-Chicago), is the most frequent abnormal Hb in this region.

Utility of serum DNA and pyrosequencing for the detection of EGFR mutations in non-small cell lung cancer.

Mutations in the EGFR gene are critical determinants of treatment with EGFR tyrosine kinase inhibitors (TKIs) for non-small cell lung cancer (NSCLC) patients. DNA isolation from tumor samples usually requires surgery; therefore, we wanted to isolate DNA from circulating tumor cells by using the serum of NSCLC patients. This protocol was recently published. DNA was isolated from the serum of 52 Turkish NSCLC patients and their EGFR mutation status was examined by pyrosequencing. EGFR mutations were detected in 25 of the 52 patients (48.1%): 17 patients with delE746-A750, 2 with delE747-A750insP, and 6 with L858R. All mutations detected by pyrosequencing were confirmed by dideoxy sequencing, and the presence of the same mutations in the tumors was verified by using paraffin embedded tissues of all the patients. Mutations were detected more frequently in adenocarcinomas (24 of 36, 66.7%) than in squamous cell carcinomas (1 of 16, 6.3%) (P<0.001). These results confirm the utility of serum DNA and pyrosequencing for the detection of EGFR mutations in patients with advanced NSCLC.

Genetic Origin of Hb D-Los Angeles [β121(GH4)Glu→Gln, GAA→CAA] According to the β-Globin Gene Cluster Haplotypes

Hb D-Los Angeles (also known as D-Punjab, D-North Carolina, D-Portugal, D-Chicago and Oak Ridge) is an abnormal hemoglobin (Hb) with an amino acid substitution of glutamine for glutamic acid at codon 121 of the β-globin gene. The origin and spread of Hb D-Los Angeles is not known. This is due to lack of information and remains to be elucidated. According to published reports, the Hb D-Los Angeles mutation is mostly linked with Mediterranean haplotype I [+ − − − − + +]. Besides the Mediterranean haplotype, a novel haplotype was also reported from Thailand [− − + + − − + + +]. Here we report a new haplotype from Turkey [− + −− + + +] that has not been described before. These results suggest that the Hb D-Los Angeles mutation has at least three different genetic origins.

Rare hemoglobin variant Hb Yaizu observed in Turkey.

Objective: To determine the characteristic features of the rare hemoglobin (Hb) variant Hb Yaizu to enable laboratory diagnosis of the hemoglobin variants during screening programs. Materials and Methods: Genomic DNA was obtained from the 4 members of a family living in Denizli province, an Aegean region of Turkey. Blood cell counts, hemoglobin composition, hemoglobin electrophoresis (both alkaline and acid), HPLC analysis, DNA sequencing and beta globin gene cluster haplotypes were done. Results: Hb Yaizu carriers were apparently healthy individuals. Hb Yaizu was slightly faster than Hb S at alkaline pH, but slower than Hb S at acidic pH in hemoglobin electrophoresis. An abnormal hemoglobin peak was observed with a retention time of 4.77 min in HPLC analysis attributed to Hb Yaizu. Two members of the family were heterozygous Hb Yaizu [beta 79(EF3) Asp>Asn] confirmed by DNA sequencing. The mutation was found to be linked with the Mediterranean haplotype I [+––––++]. Conclusion: We have presented the details of Hb Yaizu, a rare hemoglobin variant that may be important to hemoglobinopathy screening programs, although its clinical significance is unclear.

Association of a Genetic Polymorphism of the Alcohol-Metabolizing Enzyme ADH1C with Alcohol Dependence: Results of a Case-Control Study

Objective: Alcohol dependence causes serious problems which may be influenced by genetic factors associated with alcohol metabolism. The aim was to investigate the allelic and genotypic difference in distribution of a polymorphism in alcohol dehydrogenase 1C gene (ADH1C) between alcohol-dependent individuals and controls, and to examine if these genotypes were associated with the age at which the patient became alcohol-dependent. Methods: We conducted a case-control study including 90 alcohol-dependent cases and 100 historic controls. The genomic DNA was isolated and the alleles were analyzed with an RFLP. Results: The ADH1C*1 allele frequencies were 0.89 (95% CI 0.84–0.91) in controls and 0.68 (95% CI 0.61–0.74) in alcohol-dependent patients. The frequencies of the ADH1C*2 allele were 0.11 (95% CI 0.07–0.14) and 0.32 (95% CI 0.25–0.38) among controls and alcohol-dependent patients, respectively (p < 0.0001). The ADH1C*1/*1 genotype frequency was significantly higher in the control group (77%) compared to that of the alcohol-dependents (51%, p < 0.0001). The ADH1C*1/*2 genotype frequency was significantly lower in the control group (23%) compared to that of the alcohol-dependents (42%, p < 0.0001). We obtained no statistically significant difference among the ADH1C genotype groups regarding age. Conclusions: These findings suggest that a significantly higher presence of ADH1C*2 allele is associated with alcohol dependence in a Turkish population. Studies with other related polymorphisms are needed to more precisely estimate the association of alcohol dependence with ADH1C.

First observation of Hb Tunis (beta124(H2) Pro>Ser) in Turkey

Hb Tunis [beta124(H2)Pro>Ser] was reported from Tunisia in 1988. This hemoglobin variant was detected by isoelectric focusing moving just ahead of Hb A. It cannot be identified by standard hemoglobin electrophoresis due to its similar mobility to Hb A. It has normal stability and oxygen affinity and does not produce any clinical symptoms. Here, we report a heterozygous Hb Tunis [beta124(H2)Pro>Ser] case discovered for the first time in Turkey in a premarital screening program. This hemoglobin variant can be identified with high performance liquid chromatography analysis confirmed with DNA sequencing. We emphasize in our study the importance of an interdisciplinary collaborative study at the provincial basis for the success of the hemoglobinopathy control program.

FREQUENCIES OF ADH1C ALLELES AND GENOTYPES IN A TURKISH HEAD AND NECK CANCER POPULATION

Squamous cell carcinoma of the head and neck (SCCHN) have been reported to be related to both genetic and environmental factors, including alcohol consumption and alcohol-metabolizing enzymes such as alcohol dehydrogenase (ADH). We conducted a hospital-based, case-control study including 50 cases with diagnosed SCCHN and 100 controls with non-neoplastic conditions such as upper respiratory tract infection. The genomic DNA was isolated from peripheral blood leukocytes. The ADH1C*1 wild-type and ADH1C*2 variant alleles were analyzed with an RFLP method by using SspI as restriction enzyme. The ADH1C*1 allele frequencies were 0.89 (CI95% = 0.84-0.91) in controls and 0.77 (CI95% = 0.71-0.83) in cases, and respective frequencies of the ADH1C*2 allele were 0.11 (CI95% = 0.07-0.14) and 0.23 (CI95% = 0.17-0.29) among controls and cases (P = 0.01). The ADH1C*1/*1 genotype frequency was significantly higher in the control group (77%) compared to that of the cases (58%) (P = 0.02).These findings suggest that a lower presence of ADH1C*1 allele is associated with SCCHN, but larger numbers are needed to more precisely estimate the interaction, if any, with ADH1C. Interestingly, the ADH1C allele and genotype frequencies in our control group living in Denizli were significantly different compared to a previously published report from healthy volunteers living in Ankara (P < 0.0001).

An ancient anatomic variation: bilateral elongated styloid process of cranium.

The elongated stylohyoid process presents with considerable anatomic variability. We report here oil an ancient cranium with bilateral elongated styloid process, 3.3 cm on the right side and 5.1 cm on the left side, found during the examination of excavated bones of 2000 (years ago (first half of 1st century AD) from the old Greek-Roman city-of Leodikya in Turkey. We determined the gender as female, from the examination of the skeleton (especially skull and pelvic bones). No other variation was observed. On the basis of embryology, the reason for this variation may be partial ossification of the second pharyngeal arch cartilage in the region which commonly becomes the stylohyoid ligament. Although elongation of the styloid process is common, it is important to report this ancient variation, in order to help to compare the bone variations between ancient and modern humans and the contribution of genetic and environmental determinants.

Allele Frequency of VNTR Locus D1S80 Observed in Denizli Province of Turkey

The variable numbers of tandem repeats (VNTR) locus D1S80, located on chromosome 1 (1p35-36), has a repeat unit 16xa0bp in length, and different numbers of these repeat units have been observed for populations of different origins and ethnicity. We used a molecular identification method based on capillary electrophoresis separation to analyze D1S80 locus polymorphism among 74 subjects from Denizli province, Turkey, finding an amplified fragment length size of 379–635xa0bp. Allele repeat numbers were deduced from these sizes and sequence comparison. The most common alleles were repeat units 24 (34.3%) and 18 (22.4%), with frequencies of 0.414 and 0.207, respectively. Other alleles were 25 (7.86%), 28 (5.71%), 22 (4.25%), and 29 (2.86%). The allele with 23 repeat units was not observed. Results were in Hardy–Weinberg linkage disequilibrium. Observed heterozygosity was 0.614, and expected heterozygosity was 0.787. Theta(k) value was 4.86 (95% confidence interval limits). Capillary electrophoresis is a powerful approach for accurate identification of VNTR loci, especially for low base pair units like D1S80, for prenatal diagnosis, linkage analysis, forensic identification, paternity testing, anthropological research, and phylogenetic studies.

Hb Beograd [β121(GH4)Glu→Val, GAA→GTA] in the Turkish Population

Hb Beograd [β121(GH4)Glu→Val, GAA→GTA] is a rare variant first reported in Yugoslavia and then in Turkey, Australia and New Zealand. We report two further unrelated cases from Turkey. The importance of identifying Hb Beograd at the molecular level, especially in regions where Hb D-Los Angeles [β121(GH4)Glu→Gln, GAA→CAA] is prevalent, is emphasized.