Hoogeveen-Westerveld M.,Erasmus Medical Center |
Ekong R.,University College London |
Povey S.,University College London |
Mayer K.,Center for Human Genetics and Laboratory Medicine |
And 10 more authors.
Human Mutation | Year: 2013
Tuberous sclerosis complex (TSC) is an autosomal dominant disorder caused by mutations in the TSC1 or TSC2 genes. The TSC1 and TSC2 gene products, TSC1 and TSC2, form a complex that inhibits the mammalian target of rapamycin (mTOR) complex 1 (TORC1). Here, we investigate the effects of 78 TSC2 variants identified in individuals suspected of TSC, on the function of the TSC1-TSC2 complex. According to our functional assessment, 40 variants disrupted the TSC1-TSC2-dependent inhibition of TORC1. We classified 34 of these as pathogenic, three as probably pathogenic and three as possibly pathogenic. In one case, a likely effect on splicing as well as an effect on function was noted. In 15 cases, our functional assessment did not agree with the predictions of the SIFT amino acid substitution analysis software. Our data support the notion that different, nonterminating TSC2 mutations can have distinct effects on TSC1-TSC2 function, and therefore, on TSC pathology. © 2012 Wiley Periodicals, Inc.
Hoefele J.,Center for Human Genetics and Laboratory Medicine |
Wilhelm C.,CeGaT GmbH |
Heinrich U.,Center for Human Genetics and Laboratory Medicine |
Weber L.T.,Ludwig Maximilians University of Munich |
And 4 more authors.
Gene | Year: 2013
Fraser syndrome (FS) is a rare autosomal recessive inherited disorder characterized by cryptophthalmos, laryngeal defects and oral clefting, mental retardation, syndactyly, and urogenital defects. To date, 250 patients have been described in the literature. Mutations in the FRAS1 gene on chromosome 4 have been identified in patients with Fraser syndrome. So far, 26 mutations have been identified, most of them are truncating mutations. The mutational spectrum includes nucleotide substitutions, splicing defects, a large insertion, and small deletions/insertions. Moreover, single heterozygous missense mutations in FRAS1 seem to be responsible for non-syndromic unilateral renal agenesis. Here we report the first case of a family with two patients affected by Fraser syndrome due to a deletion of 64. kb (deletion 4q21.21) and an additional novel frameshift mutation in exon 66 of the FRAS1 gene. To date, large deletions of the FRAS1 gene have not yet been described. Large deletions seem to be a rare cause for Fraser syndrome, but should be considered in patients with a single heterozygous mutation. © 2013 Elsevier B.V.
Santjohanser C.,Kinderwunsch Centrum Munich |
Knieper C.,University of Heidelberg |
Franz C.,University of Heidelberg |
Hirv K.,Center for Human Genetics and Laboratory Medicine |
And 4 more authors.
Archivum Immunologiae et Therapiae Experimentalis | Year: 2013
In 1-5 % of patients during childbearing years recurrent miscarriages (RM) occur. There are established risk factors like anatomical, endocrine and hemostatic disorders as well as immunological changes in the maternal immune system. Nevertheless, further elucidation of the pathogenesis remains a matter of debate. In addition, there are no standardized immunological treatment strategies. Recent studies indicate possible effects of tumor necrosis factor α blocker and granulocyte-colony stimulating factor (G-CSF) concerning live birth rate (LBR) in RM patients. Therefore, we performed a retrospective cohort study in patients undergoing assisted reproductive treatment (ART) with known RM analysing the possible benefits of G-CSF application. From January 2002 to December 2010, 127 patients (199 cylces) with RM (at least 2 early miscarriages) 49 (72 cycles) receiving G-CSF and 78 (127 cycles) controls receiving either no medication (subgroup 1) or Cortisone, intravenous immunoglobulins or low molecular weight heparin (subgroup 2) undergoing ART for in vitro fertilisation/intracytoplasmic sperm injection were analysed. G-CSF was administered weekly once (34 Mill) in 11 patients, 38 patients received 2 × 13 Mill G-CSF per week until the 12th week of gestation. Statistical analysis was performed with SPSS for Windows (19.0), p < 0.05 significant. The mean age of the study population was 37.3 ± 4.4 years (mean ± standard deviation) and differed not significantly between patients and subgroups. However, the number of early miscarriages was significantly higher in the G-CSF group as compared to the subgroups (G-CSF 2.67 ± 1.27, subgroup 1 0.85 ± 0.91, subgroup 2 0.64 ± 0.74) and RM patients receiving G-CSF had significantly more often a late embryo transfer (day 5) (G-CSF 36.7 %, subgroup 1 12.1 %, subgroup 2 8.9 %). The LBR of patients and the subgroups differed significantly (G-CSF 32 %, subgroup 1 13 %, subgroup 2 14 %). Side effects were present in less than 10 % of patients, consisting of irritation at the injection side, slight leukocytosis, rise of the temperature (<38 C), mild bone pain and hyperemesis gravidarum. None of the newborn showed any kind of malformations. According to our data, G-CSF seems to be a safe and promising immunological treatment option for RM patients. However, with regard to the retrospective setting and the possible bias of a higher rate of late embryo transfers in the G-CSF group additional studies are needed to further strengthen our results. © 2013 L. Hirszfeld Institute of Immunology and Experimental Therapy, Wroclaw, Poland.
Toth B.,University of Heidelberg |
Wurfel W.,Kinderwunsch Centrum Munich KCM |
Germeyer A.,University of Heidelberg |
Hirv K.,Center for Human Genetics and Laboratory Medicine |
And 2 more authors.
Journal of Reproductive Immunology | Year: 2011
Recent developments in reproductive medicine address oocyte morphology, sperm analysis and embryo selection. However, in a subgroup of infertile couples, it is the embryo implantation process that is disrupted. Diagnostic tools to identify patients at risk of implantation failure are limited and therapeutic options are far away from being established. In this review we focus on selected possible causes and treatments of failed implantation. Reproductive surgery allows a proper first step diagnosis and therapy of recurrent implantation failure (RIF). Possible anatomical malformations and associated diseases with treatment options are mentioned. Diagnostic procedures in patients often focus on defining gene polymorphisms (like hereditary thrombophilia and p53) and determinants of endometrial receptivity including endometrial gene expression profiles. Although significant differences in gene expression have been identified, the study populations are quite small, some of the data conflicting and clinical significance has yet to be proven. Implantation requires a close interaction between the fetal trophoblast and the maternal endometrium with natural killer cells (NK cells) playing a main part at the feto-maternal interface during early pregnancy. Therefore this review also focuses on NK cell receptor expression and new immunmodulatory treatment options like G-CSF in RIF patients. © 2011 Elsevier Ireland Ltd.
Duebgen S.,Ludwig Maximilians University of Munich |
Kauke T.,Ludwig Maximilians University of Munich |
Marschall C.,Center for Human Genetics and Laboratory Medicine |
Giebl A.,Ludwig Maximilians University of Munich |
And 4 more authors.
American Journal of Clinical Pathology | Year: 2012
The diagnosis of thrombophilia caused by protein S deficiency remains difficult. From 2005 to 2010, we documented 135 patients with suspected hereditary protein S deficiency for whom mutational analysis of the PROS1 gene had been performed by direct double-stranded sequencing of the amplified 15 exons including splice sites. Multiplex ligation-dependent probe amplification was performed on 12 of 15 exons in cases with no mutation found but a large deletion in the PROS1 gene was suspected. Mutations were identified in 49 patients, 9 by familial screening. Altogether, 17 new and 11 previously described mutations of PROS1 were identified among the 49 patients. After the exclusion of acquired protein S deficiency due to pregnancy or hormonal contraceptives, there remained only 1 case with protein S activity levels less than 40% that could not be explained by sequence variations or deletions in the examined regions of the PROS1 gene. After the exclusion of conditions associated with acquired protein S deficiency, persistently low protein S activity levels are highly indicative of a genetic alteration in PROS1. We observed a clear correlation between the laboratory phenotype and the type of mutation. © American Society for Clinical Pathology.
PubMed | Ludwig Maximilians University of Munich, German Cancer Research Center, Center for Human Genetics and Laboratory Medicine and Helmholtz Center Munich
Type: Journal Article | Journal: Leukemia | Year: 2015
In acute myeloid leukemia (AML), several signaling pathways such as the phosphatidylinositol-3-kinase/AKT and the mammalian target of rapamycin (PI3K/AKT/mTOR) pathway are deregulated and constitutively activated as a consequence of genetic and cytogenetic abnormalities. We tested the effectiveness of PI3K/AKT/mTOR-targeting therapies and tried to identify alterations that associate with treatment sensitivity. By analyzing primary samples and cell lines, we observed a wide range of cytotoxic activity for inhibition of AKT (MK-2206), mTORC1 (rapamycin) and PI3K/mTORC1/2 (BEZ-235) with a high sensitivity of cells carrying an MLL rearrangement. In vivo PI3K/mTOR inhibition delayed tumor progression, reduced tumor load and prolonged survival in an MLL-AF9(+)/FLT3-ITD(+) xenograft mouse model. By performing targeted amplicon sequencing in 38 MLL-AF9(+) and 125 cytogenetically normal AML patient samples, we found a high additional mutation rate for genes involved in growth factor signaling in 79% of all MLL-AF9(+) samples, which could lead to a possible benefit of this cohort. PI3K/mTOR inhibition for 24h led to the cross-activation of the ERK pathway. Further in vitro studies combining PI3K/mTOR and ERK pathway inhibition revealed highly synergistic effects in apoptosis assays. Our data implicate a possible therapeutic benefit of PI3K/mTOR inhibition in the MLL-mutated subgroup. Inhibiting rescue pathways could improve the therapeutic efficacy of PI3K-targeted therapies in AML.
PubMed | University of Amsterdam, University of Tübingen, Center for Human Genetics and Laboratory Medicine, Leiden University and 3 more.
Type: Guideline | Journal: European journal of human genetics : EJHG | Year: 2015
We present, on behalf of EuroGentest and the European Society of Human Genetics, guidelines for the evaluation and validation of next-generation sequencing (NGS) applications for the diagnosis of genetic disorders. The work was performed by a group of laboratory geneticists and bioinformaticians, and discussed with clinical geneticists, industry and patients representatives, and other stakeholders in the field of human genetics. The statements that were written during the elaboration of the guidelines are presented here. The background document and full guidelines are available as supplementary material. They include many examples to assist the laboratories in the implementation of NGS and accreditation of this service. The work and ideas presented by others in guidelines that have emerged elsewhere in the course of the past few years were also considered and are acknowledged in the full text. Interestingly, a few new insights that have not been cited before have emerged during the preparation of the guidelines. The most important new feature is the presentation of a rating system for NGS-based diagnostic tests. The guidelines and statements have been applauded by the genetic diagnostic community, and thus seem to be valuable for the harmonization and quality assurance of NGS diagnostics in Europe.
Eggert M.,Ludwig Maximilians University of Munich |
Muller S.,Ludwig Maximilians University of Munich |
Heinrich U.,Center for Human Genetics and Laboratory Medicine |
Mehraein Y.,Ludwig Maximilians University of Munich
European Journal of Medical Genetics | Year: 2016
In 2012 a small terminal deletion in the short arm of chromosome 10 in the region 10p15.3 was reported as a novel microdeletion syndrome. By now 21 patients, including a single familial case, have been reported. Characteristic findings comprise variable cognitive impairment or developmental delay, disorder of speech development, as well as various dysmorphic signs. We here report on a new patient, an eight year old girl, with a microdeletion syndrome 10p15.3. She is a foster child showing intellectual deficits, disorder of speech development, behavioral problems, congenital heart defect, and several dysmorphic signs. The same microdeletion was subsequently found in the six year old maternal half-sister, showing very similar developmental and cognitive issues, including major speech impairment. The mother has not obtained a school degree. She was described as being a dissocial person with severe alcohol abuse and showing minor cognitive disability. Thus inheritance of the microdeletion from a probably symptomatic mother can be assumed. The patients presented here add up to the as yet small number of reported cases of microdeletion 10p15.3 and thereby might help to establish a more comprehensive clinical spectrum of this rather newly discovered syndrome. © 2016 Elsevier Masson SAS.
Grumbt B.,Center for Human Genetics and Laboratory Medicine |
Eck S.H.,Center for Human Genetics and Laboratory Medicine |
Hinrichsen T.,Center for Human Genetics and Laboratory Medicine |
Hirv K.,Center for Human Genetics and Laboratory Medicine
Transfusion Medicine and Hemotherapy | Year: 2013
With the introduction of the next generation sequencing (NGS) technologies, remarkable new diagnostic applications have been established in daily routine. Implementation of NGS is challenging in clinical diagnostics, but definite advantages and new diagnostic possibilities make the switch to the technology inevitable. In addition to the higher sequencing capacity, clonal sequencing of single molecules, multiplexing of samples, higher diagnostic sensitivity, workflow miniaturization, and cost benefits are some of the valuable features of the technology. After the recent advances, NGS emerged as a proven alternative for classical Sanger sequencing in the typing of human leukocyte antigens (HLA). By virtue of the clonal amplification of single DNA molecules ambiguous typing results can be avoided. Simultaneously, a higher sample throughput can be achieved by tagging of DNA molecules with multiplex identifiers and pooling of PCR products before sequencing. In our experience, up to 380 samples can be typed for HLA-A, -B, and -DRB1 in high-resolution during every sequencing run. In molecular oncology, NGS shows a markedly increased sensitivity in comparison to the conventional Sanger sequencing and is developing to the standard diagnostic tool in detection of somatic mutations in cancer cells with great impact on personalized treatment of patients. © 2013 S. Karger GmbH, Freiburg.
PubMed | Ludwig Maximilians University of Munich and Center for Human Genetics and Laboratory Medicine
Type: Case Reports | Journal: European journal of medical genetics | Year: 2016
In 2012 a small terminal deletion in the short arm of chromosome 10 in the region 10p15.3 was reported as a novel microdeletion syndrome. By now 21 patients, including a single familial case, have been reported. Characteristic findings comprise variable cognitive impairment or developmental delay, disorder of speech development, as well as various dysmorphic signs. We here report on a new patient, an eight year old girl, with a microdeletion syndrome 10p15.3. She is a foster child showing intellectual deficits, disorder of speech development, behavioral problems, congenital heart defect, and several dysmorphic signs. The same microdeletion was subsequently found in the six year old maternal half-sister, showing very similar developmental and cognitive issues, including major speech impairment. The mother has not obtained a school degree. She was described as being a dissocial person with severe alcohol abuse and showing minor cognitive disability. Thus inheritance of the microdeletion from a probably symptomatic mother can be assumed. The patients presented here add up to the as yet small number of reported cases of microdeletion 10p15.3 and thereby might help to establish a more comprehensive clinical spectrum of this rather newly discovered syndrome.