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Michael Klintschar

Publications and source records attributed to Michael Klintschar.

14 recordsLinked to original sources
PubMed2006

Y-chromosomal STR haplotype analysis reveals surname-associated strata in the East-German population.

In human populations, the correct historical interpretation of a genetic structure is often hampered by an almost inherent inability to differentiate between ancient and more recent influences upon extant gene pools. One method to trace recent population movements is the analysis of surnames, which, at least in Central Europe, can be thought of as traits 'linked' to the Y chromosome. Illegitimacy, extramarital birth and changes of surnames may have substantially obscured this linkage. In order to assess the actual extent of correlation between surnames and Y-chromosomal haplotypes in Central Europe, we typed Y-chromosomal short tandem repeat markers in 419 German males from Halle. These individuals were subdivided into three groups according to the origin of their respective surname, namely German (G), Slavic (S) or 'Mixed' (M). The distribution of the haplotypes was compared by Analysis of Molecular Variance. While the M group was indistinguishable from group G (PhiST=-0.0008, P>0.5), a highly significant difference (PhiST=0.0277, P<0.001) was observed between the S group and the combined G+M group. This surprisingly strong differentiation is comparable to that of European populations of much larger geographic and linguistic difference. In view of the major migration from Slavic countries into Germany in the 19th century, it appears likely that the observed concurrence of Slavic surnames and Y chromosomes is of a recent rather than an early origin. Our results suggest that surnames may provide a simple means to stratify, and thereby to render more efficient, Y-chromosomal analyses of Central Europeans that target more ancient events.

Chromosomes, Human, Y↗
PubMed2006

Fetal microchimerism in Hashimoto's thyroiditis: a quantitative approach.

OBJECTIVE: Fetal microchimerism (MCH) has been implicated in the etiology of autoimmune diseases such as autoimmune thyroiditis. The goal of the study was to reliably estimate the number of fetal engrafted cells and to further investigate factors influencing the development of MCH. METHODS: Quantitative real-time PCR amplification using Y-chromosome specific (DYS14) and autosomal (beta-globin) loci was performed on thyroid gland specimens. Furthermore, we compared the distribution of ABO and rhesus systems in mothers with and without blood MCH in relation to the blood groups of the children. RESULTS: MCH was detected in eight of 21 Hashimoto patients in a frequency range of 15 to 4900 male cells per 100,000 total cells (median 97 cells), but in none of 17 healthy thyroid glands. In a third group, consisting of 18 nodular goiters, only one sample was positive (182 male cells/100,000 total cells). No woman who had not had a prior pregnancy with a male fetus showed MCH. Mothers both with and without MCH showed the same rate of mother/child incompatibilities for the ABO and rhesus systems. CONCLUSIONS: The percentage of microchimeric cells varies to a great extent in Hashimoto's thyroiditis, and this phenomenon can occur in nodular goiter in rare instances, but it appears to be absent from normal thyroid glands. Nevertheless, the biological significance of MCH remains unclear. Moreover, we have concluded that the tested blood group systems (as opposed to their role in graft vs host disease after transplantations) have no effect on fetal MCH.

ABO Blood-Group System↗
PubMed2005

Y chromosome polymorphisms and haplotypes in South Saxony-Anhalt (Germany).

We have performed a population genetic study on a population from South Saxony-Anhalt, Germany. The allele distributions of the systems DYS19, DYS385, DYS389I/II DYS390, DYS391, DYS392 and DYS393 were investigated in a sample of 234 unrelated males. PCR products were detected using capillary electrophoresis on the ABI Prism 310 DNA sequencer. Two hundred and six different haplotypes were obtained. The haplotype diversity was 0.8915. Using AMOVA significant differences were observed to populations from Poland and Croatia.

Chromosomes, Human, Y↗
PubMed2005

TH01, a tetrameric short tandem repeat locus in the tyrosine hydroxylase gene: association with myocardial hypertrophy and death from myocardial infarction?

TH01 is a tetrameric short tandem repeat locus located in intron 01 of the tyrosine hydroxylase gene. The tyrosine hydroxylase catalyzes the hydroxylation of L-tyrosine to L-DOPA and is the rate limiting enzyme in the synthesis of catecholamines like noradrenaline or adrenaline, which are pivotal in the regulation of blood pressure. In a clinical study a strong correlation between alleles *9.3 and *10 and essential hypertension was observed ([2] Hypertension 32: 676-682). To further investigate this association, we typed TH01 in 296 autopsy cases and correlated the genotypes to the heart weight as parameter for myocardial hypertrophy. No significant correlation was observed. Moreover, dividing the studied cases into 2 groups, one including 172 casualties from hypertension-associated diseases (myocardial infarction, left heart failure, aortic aneurysm, spontaneous intracerebral bleeding and cerebral infarction) and one consisting of 124 cases of death unrelated to hypertension, revealed similar allelic frequencies for both groups. Our data thus suggest that TH01 long alleles appear not to lead to a significant increase in the incidence of myocardial hypertrophy or other hypertension associated diseases. This could be explained by a relatively small impact of the TH01 genotype on the blood pressure or by counteraction of another mechanism related to catecholamines and their effect on the human body.

Adult↗
PubMed2005

Expression of the epidermal growth factor seven-transmembrane member CD97 correlates with grading and staging in human oral squamous cell carcinomas.

INTRODUCTION: The oral squamous cell carcinoma (OSCC) is the sixth most common malignant tumor worldwide. No significant better progress has been made in the treatment of OSCCs during the last decades. The heterodimeric CD97 protein is a epidermal growth factor seven-transmembrane family member and was identified as a dedifferentiation marker in thyroid carcinomas. Nothing is known about CD97 in OSCCs. MATERIAL AND METHODS: Employing UV-laser microdissection, CD97 and its ligand CD55 were investigated in normal oral mucosa and OSCCs (n = 78) by multiplex reverse transcription-PCR. Frozen sections were investigated by immunohistochemistry. The effects of retinoic acid and sodium butyrate on the CD97/CD55 expression in OSCC cell lines were determined by quantitative PCR, immunocytochemistry, and flow cytometry. RESULTS: Weak CD97 transcripts were expressed in normal mucosa and normal basal epithelial cells revealed specific CD97 immunostaining. Strong CD97 transcripts were detected in pT(3)/T(4) and G3/G4 OSCC tissues, whereas pT(1)/T(2) and G1/G2 carcinomas revealed weak CD97 transcript levels. A weak CD97 immunostaining was observed in pT(1)/T(2) and G1/G2 tumors. By contrast, intensive CD97 immunostaining was detected in pT(3)/T(4) OSCCs and G3/G4 lesions. CD55 gene expression was low in normal mucosa. All OSCCs, irrespective of stage and grading, displayed strong CD55 immunostaining. Sodium butyrate and retinoic acid inhibited CD97 mRNA and protein in OSCC cell lines. Interestingly, CD55 was up-regulated by both substances. CONCLUSION: We identified CD97 as a novel marker of dedifferentiated OSCC. Interaction of CD97 and CD55 may facilitate adhesion of OSCC cells to surrounding surfaces that would result in metastases and bad prognosis.

Adult↗
PubMed2004

Haplotype studies support slippage as the mechanism of germline mutations in short tandem repeats.

Germline mutations of human short tandem repeat (STR) loci are expansions or contractions of repeat arrays which are not well understood in terms of the mechanism(s) underlying such mutations. Although polymerase slippage is generally accepted as a mechanism capable to explain most features of such mutations, it is still possible that unequal crossing over plays some role in those events, as most studies in humans could not exclude unequal crossing over (UCO). Crossing over can be studied by analyzing haplotypes using flanking markers. To check for UCO in mutations, we have analyzed 150 paternity cases for which more than the usual trio (mother, child, and father) were available for testing by analyzing 16 STR loci. In a total of 4900 parent-child allele transfers four mutations were observed at different loci (D8S1179, D18S51, D21S11, and SE33/ACTBP2). To identify the mutated allele and to check for UCO, we typed at least four informative loci flanking the mutated locus and used the pedigree data to establish haplotypes. By doing so we were able to exclude UCO in each case. Moreover, we were able to identify the mutations as one-repeat contractions/expansions. Our data thus support slippage as the mechanism of germline mutations in STRs.

Crossing Over, Genetic↗
PubMed2003

Polymerase slippage in relation to the uniformity of tetrameric repeat stretches.

The aim of the study was to test the hypothesis that polymerase slippage correlates to the length of repeat stretches consisting of uniform repeats against the alternative hypothesis that the total number of repeats is most relevant. Two short tetrameric short tandem repeats (STRs) with different repeat structures were investigated: D3S1545 containing only homogeneous (GATA)n repeat stretches and D7S1517 with compound repeat arrays of GAAA and CAAA repeats. Additionally two different polymerases (Herculase and AmpliTaq Gold) were used which gave comparable results. No correlation was found for the hypothesis "total repeat number against percent of stutter"; in contrast, the other hypothesis that the number of uniform repeats is relevant for the degree of stutter gave a strong positive correlation (0.82 for selected D7S1517 alleles) which confirmed the hypothesis that polymerase slippage correlates to the length of repeat stretches consisting of uniform repeats.

Alleles↗
PubMed2003

Population data on the AmpFlSTR SGM plus PCR amplification kit in Germans and Austrians.

Allele frequencies for the short tandem repeat loci D3S1358, VWA, D16S539, D2S1338, D8S1179, D21S11, D18S51, D19S433, THO1 and FGA were determined in 231 German and 100 Austrian unrelated Caucasoids using the AmpFlSTR SGM plus kit (Applied Biosystems). All loci met Hardy-Weinberg expectations. In 212 meioses per locus, one mutation event for D19S433 was observed.

Austria↗
PubMed2003

Asian online Y-STR Haplotype Reference Database.

For several years Y-chromosomal microsatellites (short tandem repeats, STRs) have been well established in forensic practice. In this context, the genetic characteristics of the Y chromosome (i.e. its paternal inheritance and lack of recombination) render STRs particularly powerful. However, genetic differences between male populations appear to be larger for Y-STRs than for autosomal STRs, a fact that is most likely due to the higher sensitivity of Y-chromosomal lineages to genetic drift (Forensic Sci Int 118 (2001) 153). The assessment of probabilities for matches between haplotyped male persons or traces/persons requires the typing of a large number of haplotypes in the appropriate reference populations. The haplotype data of a large number of European as well as South and North American populations have been collected and are continuously published online (Y-STR Haplotype Reference Database--YHRD; http://www.ystr.org). The most recent multicentric effort has led to the establishment of an Asian YHRD (http://www.ystr.org/asia) which has been available since January 2002. All databases are maintained and curated at the Institute of Legal Medicine, Humboldt-University, Berlin and will soon be fused to a global repository including populations from all continents.

Asia↗
PubMed2003

[Therapy of head injuries caused by animal slaughter guns].

Slaughterer's guns ("humane killers") are powder-activated cattle skull impacting tools. Today mechanical stunning is typical for country like regions, because in the municipal slaughter-houses electrical stunning of pigs and ruminants is preferred. In rare cases these weapons are used for suicide. They then cause penetrating brain lesions and if the victim survives the brain-damage, an encephalitis caused by the impacted material results. The neurosurgical treatment is to revise the gunshot canal and to remove impacted fragments of bone and contaminated skin (imprimat) under antibiotic cover. A psychiatric treatment of the mostly underlying depression and a rehabilitative treatment should complete therapy. So treatment of slaughterer's gun injury should have a multidisciplinary approach.

Abattoirs↗
PubMed2003

Identification of forensic samples by using an infrared-based automatic DNA sequencer.

We have recently introduced a new protocol for analyzing all core loci of the Federal Bureau of Investigation's (FBI) Combined DNA Index System (CODIS) with an infrared (IR) automatic DNA sequencer (LI-COR 4200). The amplicons were labeled with forward oligonucleotide primers, covalently linked to a new infrared fluorescent molecule (IRDye 800). The alleles were displayed as familiar autoradiogram-like images with real-time detection. This protocol was employed for paternity testing, population studies, and identification of degraded forensic samples. We extensively analyzed some simulated forensic samples and mixed stains (blood, semen, saliva, bones, and fixed archival embedded tissues), comparing the results with donor samples. Sensitivity studies were also performed for the four multiplex systems. Our results show the efficiency, reliability, and accuracy of the IR system for the analysis of forensic samples. We also compared the efficiency of the multiplex protocol with ultraviolet (UV) technology. Paternity tests, undegraded DNA samples, and real forensic samples were analyzed with this approach based on IR technology and with UV-based automatic sequencers in combination with commercially-available kits. The comparability of the results with the widespread UV methods suggests that it is possible to exchange data between laboratories using the same core group of markers but different primer sets and detection methods.

DNA Fingerprinting↗
PubMed2002

Population genetic data, comparison of the repeat structure and mutation events of two short STRs.

The short tandem repeat (STR) systems D3S1545 and D7S1517, both small size STRs (fragment lengths <160 bp), were investigated in a population sample of German Caucasoids. New primer sequences more closely flanking the repetitive region were designed for D3S1545. For D3S1545, 7 alleles could be found (heterozygosity 0.68) while 11 alleles could be typed for D7S1517 (heterozygosity 0.83). Additionally, sequencing of selected alleles was carried out to establish the allele nomenclature and to clarify the structure of the tandem repeat arrays. D3S1545 showed a uniform GATA repeat structure but, in contrast, the repeat stretch of D7S1517 showed a compound structure characterised by different numbers of GAAA and CAAA repeats. Two isolated cases of a new mutation could be confirmed for D7S1517. The alleles of these two family constellations were characterised by sequencing and the probable mutational events were demonstrated.

Adolescent↗
PubMed2002

Y-chromosome analysis in Egypt suggests a genetic regional continuity in Northeastern Africa.

The geographic location of Egypt, at the interface between North Africa, the Middle East, and southern Europe, prompted us to investigate the genetic diversity of this population and its relationship with neighboring populations. To assess the extent to which the modern Egyptian population reflects this intermediate geographic position, ten Unique Event Polymorphisms (UEPs), mapping to the nonrecombining portion of the Y chromosome, have been typed in 164 Y chromosomes from three North African populations. The analysis of these binary markers, which define 11 Y-chromosome lineages, were used to determine the haplogroup frequencies in Egyptians, Moroccan Arabs, and Moroccan Berbers and thereby define the Y-chromosome background in these regions. Pairwise comparisons with a set of 15 different populations from neighboring European, North African, and Middle Eastern populations and geographic analysis showed the absence of any significant genetic barrier in the eastern part of the Mediterranean area, suggesting that genetic variation and gene flow in this area follow the "isolation-by-distance" model. These results are in sharp contrast with the observation of a strong north-south genetic barrier in the western Mediterranean basin, defined by the Gibraltar Strait. Thus, the Y-chromosome gene pool in the modern Egyptian population reflects a mixture of European, Middle Eastern, and African characteristics, highlighting the importance of ancient and recent migration waves, followed by gene flow, in the region.

Arabs↗