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Dive into the research topics where Regine Witkowski is active.

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Featured researches published by Regine Witkowski.


Cancer Genetics and Cytogenetics | 1992

Karyotypes in 90 human gliomas

Gundula Thiel; Tanka Losanowa; Dieter Kintzel; Gunter Nisch; Hubert Martin; Klaus Vorpahl; Regine Witkowski

Cytogenetic studies were performed on 90 human gliomas including 26 astrocytomas, 12 oligodendrogliomas, three oligo-astrocytomas, seven ependymomas, eight pilocytic astrocytomas, and 33 malignant gliomas (anaplastic astrocytomas and glioblastomas). The most common abnormalities were trisomy 7 in 23 cases, monosomy 22 in 15 cases, losses of the Y chromosome in 19 of 50 male cases, and losses of the X chromosome in 10 of 39 female cases. There are evident differences between the particular subgroups of gliomas. Monosomy 10 and double minutes are typical for malignant gliomas. The 58 determined chromosomal breakpoints were located on 45 different sites. Chromosomes 1, 9, 6, 3, 10, and 17 were predominantly involved.


Genes, Chromosomes and Cancer | 1996

Recurrent gain of chromosome arm 7q in low‐grade astrocytic tumors studied by comparative genomic hybridization

Evelin Schröck; Collin Blume; Marie-Christine Meffert; Stanislas du Manoir; Wolf Bersch; Marika Kiessling; Tanka Lozanowa; Gundula Thiel; Regine Witkowski; Thomas Ried; Thomas Cremer

Consistent tumor‐specific chromosomal aberrations have not been described in low‐grade astrocytic tumors. The most frequent genetic alterations are mutations of the TP53 tumor suppressor gene and/or loss of heterozygosity (LOH) on 17p that occur in about 30% of the cases in adult patients but that are uncommon in childhood tumors. We used comparative genomic hybridization (CGH) to map DNA copy number alterations in 18 primary low‐grade astrocytic tumors (ten adult patients and eight children). A gain of chromosome arm 7q was the most frequent event detected in five of ten astrocytomas (50%) from adult patients, followed by DNA amplification on chromosome arm 8q and gain on 12p (two cases). Loss of chromosomal regions on 1p, 4q, and the X chromosome was observed in two of ten cases each [including one patient afflicted with Turner syndrome (45,X)]. In contrast, no consistent changes were observed in low‐grade astrocytomas in children. A loss of the X chromosome was the sole aberration detected in two of eight cases using DNA extracted from normal brain tissue. The findings suggest that a gain of 7q is an early event in the initiation of astrocytomas in adult patients. The discrepant findings in low‐grade astrocytic tumors in adults compared to tumors in children support the hypothesis that there might be different mechanisms responsible for tumor development. Genes Chromosom Cancer 15:199–205 (1996).


Human Genetics | 1983

Deficiency, transposition, and duplication of one 15q region may be alternatively associated with Prader-Willi (or a similar) syndrome. Analysis of seven cases after varying ascertainment

M. Fraccaro; O. Zuffardi; E. Bühler; Albert Schinzel; G. Simoni; Regine Witkowski; E. Bonifaci; D. Caufin; G. Cignacco; N. Delendi; L. Gargantini; T. Losanowa; L. Marca; Eva Ullrich; V. Vigi

SummarySeven patients are described who have some or all of the symptoms of Prader-Willi syndrome. They were ascertained by varying criteria starting either from the clinical picture or from the identification of a chromosome abnormality involving the proximal portion of the long arm of chromosome 15. The chromosome abnormalities consisted of two balanced translocations (15;18 and 8;15), three unbalanced ones (15;18, 15;19, and 9;15), and one interstitial deletion of bands 15q11 and q12. The seventh case had an unidentified extra chromosome. These data and a review of the literature led to the conclusion that deficiency, transposition, and even duplication of the region(s) 15q11-q13 may all result in a syndrome which is identifiable with or similar to the Prader-Willi syndrome.


Cancer Genetics and Cytogenetics | 1995

Involvement of chromosome 22 in ependymomas

Catrin Wernicke; Gundula Thiel; Tanka Lozanova; Siegfried Vogel; Dieter Kintzel; Werner Jänisch; Karin Lehmann; Regine Witkowski

We have karyotyped a total of twelve ependymomas using GTG-banding including seven for which preliminary results have already been published. One case showing hyperdiploid main line with two marker chromosomes was further analyzed by nonisotopic chromosome in situ suppression hybridization. It was shown that the marker chromosomes consisted of 1q, 14q and 1q, and 22q. The possible role of chromosome 22 in ependymomas and the usefulness of fluorescence in situ hybridization for cytogenetic analysis in tumor investigation are discussed.


Genes, Chromosomes and Cancer | 1997

Numerical aberrations of chromosomes 1, 2, and 7 in astrocytomas studied by interphase cytogenetics.

Catrin Wernicke; Gundula Thiel; Tanka Lozanova; Siegfried Vogel; Regine Witkowski

For both juvenile astrocytomas and astrocytomas of adults, numerical and structural aberrations of chromosomes 1 and 7 have been described. To study the frequency of those aberrations in more detail and to exclude in vitro artifacts, we investigated directly prepared material from 18 juvenile and 26 astrocytomas of adults by fluorescence in situ hybridization with DNA probes specific for chromosome regions 1p36, 1q12, 2cen, and 7cen. Chromosome 2 was used as control in the hybridization with chromosome 7. To exclude tissue‐specific alterations, we tested cerebral and cerebellar paraffin‐embedded material from persons who had died from other diseases. In 13 of the juvenile astrocytomas, we found a loss of 1p36 in relation to 1q12. In 16 astrocytomas of adults, a gain of signals from 1p36 or both probes for chromosome 1 was seen. Gain of chromosome 7 was found in 25 cases. Unexpectedly, gain of chromosome 2 occurred in 32 cases. For both probes, there was no difference between astrocytomas of children and those of adults. Our data suggest that loss of 1p is an early event in the development of juvenile astrocytomas and that trisomy 7 is frequent in malignant tumors and tumors containing a potential of growing malignantly. Genes Chromosom. Cancer 19:6–13, 1997.


American Journal of Medical Genetics | 1998

Bilaterally cleft lip, limb defects, and haematological manifestations: Roberts syndrome versus TAR syndrome

Maik Urban; Charlotte Opitz; Christiane Bommer; Herbert Enders; Sigrid Tinschert; Regine Witkowski

We report on a 13-year-old patient followed since birth. He is the only offspring of young, non-consanguineous German parents. His mother has an isolated left cleft of lip and a cleft palate. At birth, our patient presented with bilaterally cleft lip/cleft palate, phocomelia of upper limbs with normal hands, and mild symmetrical deficiencies of the long bones of the lower limbs. Haematological evaluation demonstrated a leukaemoid reaction during a urinary tract infection as well as intermittent thrombocytopenia and episodes of marked eosinophilia during the first two years of life. Intellectual development has been normal. Comparison with two similar cases from the literature suggests a non-random phenotypic overlap of Roberts syndrome (MIM 268300) and TAR syndrome (MIM 274000). Such clinical constellations may be key observations to understand the genetic relationship of Roberts syndrome and TAR syndrome in future phenotype-genotype correlations.


Human Genetics | 1993

Age-related nonrandom chromosomal abnormalities in human low-grade astrocytomas

Gundula Thiel; Tanka Lozanova; Siegfried Vogel; Dieter Kintzel; Werner Jänisch; Regine Witkowski

We report a cytogenetic investigation of 55 low-grade astrocytomas in 52 patients, 15 children and 37 adults. In addition to numerical aberrations such as trisomy 7 and gonosomal losses, we found structural and/or numerical aberrations of chromosome 1 in eight astrocytomas. There was a striking difference between the rearranged chromosomes in pediatric and adult patients. Whereas the pediatric tumors revealed monosomies 1p with accompanying trisomy 1q, the astrocytomas in adults showed partial or complete monosomies 1q.


Human Genetics | 1986

Maternal serum alpha-fetoprotein screening for neural tube defects and other disorders using an ultramicro-ELISA

Hannelore Körner; Lidia Rodriguez; J. L. Fernandez Yero; Margarete Schulze; Anton Horn; Luis Heredero; Regine Witkowski; Sigrid Tinschert; J. Oliva; Dietlind Sommer; R. Solis; Ch. Zwahr; P. Prenzlau; G. Cobet; H. Günther

SummaryIn Cuba and in the German Democratic Republic (GDR) a total of 24,412 pregnant women were tested for maternal serum alpha-fetoprotein (MSAFP) at the 16th to 20th week of gestation. An inexpensive and partly automated ultramicroliter enzyme immunoassay (ELISA) with final volumes of 10μl was used to analyze simultaneously 50 samples. The intraassay coefficient of variation (CV) of 5–8% and day/day CVs of 6–10.5% were obtained with a test frequency of 320 assays/day. A cut-off level of twice the median value (MoM) was chosen. An amniocentesis was done in a total of 0.5% (in the GDR) and 0.7% (in Cuba) of the screened women. The prevalence of open neural tube defects (ONTD) was calculated from the present study and was 1.43‰ in Cuba and 1.34‰ in the GDR. Through MSAFP screening 88.2% ONTD were detected. There was no therapeutic abortion of a normal fetus. The approximate cost for this program was about 2.36 marks-GDR per patient screened, or about 2,048 marks per ONTD detected.


Human Genetics | 1978

Ring chromosome 3 in a retarded boy

Regine Witkowski; Eva Ullrich; Ursula Piede

SummaryWe present a boy with the karyotype 46,XY,r3 and a phenotype with psychomotor and growth retardation, craniofacial anomalies, syndactyly of the toes, and edema of the feet. The karyotypes and phenotypes of both parents are normal.


Mund-, Kiefer- Und Gesichtschirurgie | 1998

Das Nager-Syndrom

Charlotte Opitz; D. D. Shetty; Regine Witkowski

Gegenstand der Arbeit waren eine Literaturanalyse zum Nager-Syndrom sowie eine Auswertung von 6 eigenen Patienten mit dieser angeborenen Fehlbildung zur Symptomatik, Ätiologie und Pathogenese. Die für die Differentialdiagnose in Betracht kommenden Erkrankungen wurden aufgeführt. Die Klärung der Ätiologie dieser angeborenen Fehlbildung steht noch aus. Molekulargenetische Untersuchungen bei entsprechenden Patienten sind möglicherweise der Schlüssel für zukünftige neue Erkenntnisse. Zum Erfolg interdisziplinärer kieferchirurgisch-kieferorthopädischer Maßnahmen wird anhand einer Kasuistik Stellung genommen. Möglichkeiten und Probleme der Therapie werden an diesem Beispiel aufgezeigt. In this publication, Nager syndrome was analyzed in the literature and six patients from our clinic were evaluated in relation to symptoms, etiology and pathogenesis. The diseases to be considered when making a differential diagnostis are pointed out. Clarification of the etiology is still pending. Molecular genetic research in these patients is possibly the key for new findings. A case report illustrates the results of interdisciplinary treatment by the surgeon and orthodontist. Possibilities and problems in relation to therapy are demonstrated.

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Gundula Thiel

Humboldt University of Berlin

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Eva Ullrich

Humboldt University of Berlin

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Prokop O

Humboldt University of Berlin

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Charlotte Opitz

Humboldt University of Berlin

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Sigrid Tinschert

Humboldt University of Berlin

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Siegfried Vogel

Humboldt University of Berlin

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Tanka Lozanova

Humboldt University of Berlin

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Dieter Kintzel

Humboldt University of Berlin

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Werner Jänisch

Humboldt University of Berlin

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