977 resultados para Phenotypic


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Multiple endocrine neoplasia type 2 is characterized by germline mutations in RET. For exon 10, comprehensive molecular and corresponding phenotypic data are scarce. The International RET Exon 10 Consortium, comprising 27 centers from 15 countries, analyzed patients with RET exon 10 mutations for clinical-risk profiles. Presentation, age-dependent penetrance, and stage at presentation of medullary thyroid carcinoma (MTC), pheochromocytoma, and hyperparathyroidism were studied. A total of 340 subjects from 103 families, age 4-86, were registered. There were 21 distinct single nucleotide germline mutations located in codons 609 (45 subjects), 611 (50), 618 (94), and 620 (151). MTC was present in 263 registrants, pheochromocytoma in 54, and hyperparathyroidism in 8 subjects. Of the patients with MTC, 53% were detected when asymptomatic, and among those with pheochromocytoma, 54%. Penetrance for MTC was 4% by age 10, 25% by 25, and 80% by 50. Codon-associated penetrance by age 50 ranged from 60% (codon 611) to 86% (620). More advanced stage and increasing risk of metastases correlated with mutation in codon position (609-620) near the juxtamembrane domain. Our data provide rigorous bases for timing of premorbid diagnosis and personalized treatment/prophylactic procedure decisions depending on specific RET exon 10 codons affected. Hum Mutat 32:51-58, 2011. (C) 2010 Wiley-Liss, Inc.

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Context: GLI2 is a transcription factor downstream in Sonic Hedgehog signaling, acting early in ventral forebrain and pituitary development. GLI2 mutations were reported in patients with holoprosencephaly (HPE) and pituitary abnormalities. Objective: The aim was to report three novel frameshift/nonsense GLI2 mutations and the phenotypic variability in the three families. Setting: The study was conducted at a university hospital. Patients and Methods: The GLI2 coding region of patients with isolated GH deficiency (IGHD) or combined pituitary hormone deficiency was amplified by PCR using intronic primers and sequenced. Results: Three novel heterozygous GLI2 mutations were identified: c. 2362_2368del p. L788fsX794 (family 1), c. 2081_2084del p. L694fsX722 (family 2), and c. 1138 G > T p. E380X (family 3). All predict a truncated protein with loss of the C-terminal activator domain. The index case of family 1 had polydactyly, hypoglycemia, and seizures, and GH, TSH, prolactin, ACTH, LH, and FSH deficiencies. Her mother and seven relatives harboring the same mutation had polydactyly, including two uncles with IGHD and one cousin with GH, TSH, LH, and FSH deficiencies. In family 2, a boy had cryptorchidism, cleft lip and palate, and GH deficiency. In family 3, a girl had hypoglycemia, seizures, excessive thirst and polyuria, and GH, ACTH, TSH, and antidiuretic hormone deficiencies. Magnetic resonance imaging of four patients with GLI2 mutations and hypopituitarism showed a hypoplastic anterior pituitary and an ectopic posterior pituitary lobe without HPE. Conclusion: We describe three novel heterozygous frameshift or nonsense GLI2 mutations, predicting truncated proteins lacking the activator domain, associated with IGHD or combined pituitary hormone deficiency and ectopic posterior pituitary lobe without HPE. These phenotypes support partial penetrance, variable polydactyly, midline facial defects, and pituitary hormone deficiencies, including diabetes insipidus, conferred by heterozygous frameshift or nonsense GLI2 mutations. (J Clin Endocrinol Metab 95: E384-E391, 2010)

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The role of physiological understanding in improving the efficiency of breeding programs is examined largely from the perspective of conventional breeding programs. Impact of physiological research to date on breeding programs, and the nature of that research, was assessed from (i) responses to a questionnaire distributed to plant breeders and physiologists, and (ii) a survey of literature abstracts. Ways to better utilise physiological understanding for improving breeding programs are suggested, together with possible constraints to delivering beneficial outcomes. Responses from the questionnaire indicated a general view that the contribution by crop physiology to date has been modest. However, most of those surveyed expected the contribution to be larger in the next 20 years. Some constraints to progress perceived by breeders and physiologists were highlighted. The survey of literature abstracts indicated that from a plant breeding perspective, much physiological research is not progressing further than making suggestions about possible approaches to selection. There was limited evidence in the literature of objective comparison of such suggestions with existing methodology, or of development and application of these within active breeding programs. It is argued in this paper that the development of outputs from physiological research for breeding requires a good understanding of the breeding program(s) being serviced and factors affecting its performance. Simple quantitative genetic models, or at least the ideas they represent, should be considered in conducting physiological research and in envisaging and evaluating outputs. The key steps of a generalised breeding program are outlined, and the potential pathways for physiological understanding to impact on these steps are discussed. Impact on breeding programs may arise through (i) better choice of environments in which to conduct selection trials, (ii) identification of selection criteria and traits for focused introgression programs, and (iii) identifying traits for indirect selection criteria as an adjunct to criteria already used. While many breeders and physiologists apparently recognise that physiological understanding may have a major role in the first area, there appears to be relatively Little research activity targeting this issue, and a corresponding bias, arguably unjustified, toward examining traits for indirect selection. Furthermore, research on traits aimed at crop improvement is often deficient because key genetic parameters, such as genetic variation in relevant breeding populations and genetic (as opposed to phenotypic) correlations with yield or other characters of economic importance, are not properly considered in the research. Some areas requiring special attention for successfully interfacing physiology research with breeding are discussed. These include (i) the need to work with relevant genetic populations, (ii) close integration of the physiological research with an active breeding program, and (iii) the dangers of a pre-defined or narrow focus in the physiological research.

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The genetic mechanisms responsible for the formation of adrenocortical adenomas which autonomously produce aldosterone are largely unknown, The adrenal renin-angiotensin system has been implicated in the pathophysiology of these tumours, Angiotensin-converting enzyme (ACE) catalyses the generation of angiotensin II, and the insertion/deletion (I/D) polymorphism of the ACE gene regulates up to 50% of plasma and cellular ACE variability in humans. We therefore examined the genotypic and allelic frequency distributions of the ACE gene I/D polymorphism in 55 patients with aldosterone-producing adenoma, APA, (angiotensin-unresponsive APA n = 28, angiotensin-responsive APA n = 27), and 80 control subjects with no family history of hypertension, We also compared the ACE gene I/D polymorphism allelic pattern in matched tumour and peripheral blood DNA in the 55 patients with APA, The frequency of the D allele was 0.518 and 0.512 and the I allele was 0.482 and 0.488 in the APA and control subjects respectively, Genotypic and allelic frequency analysis found no significant differences between the groups, Examination of the matched tumour and peripheral blood DNA samples revealed the loss of the insertion allele in four of the 25 patients who were heterozygous for the ACE I/D genotype. The I/D polymorphism of the ACE gene does not appear to contribute to the biochemical and phenotypic characteristics of APA, however, the deletion of the insertion allele of the ACE gene I/D polymorphism in 16% of aldosterone-producing adenomas may represent the loss of a tumour suppressor gene/s or other genes on chromosome 17q which may contribute to tumorigenesis in APA.

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This report describes the identification of a murine cytomegalovirus (MCMV) G protein-coupled receptor (GCR) homolog. This open reading frame (M33) is most closely related to, and collinear with, human cytomegalovirus UL33, and homologs are also present in human herpesvirus 6 and 7 (U12 for both viruses). Conserved counterparts in the sequenced alpha- or gammaherpesviruses have not been identified to date, suggesting that these genes encode proteins which are important for the biological characteristics of betaherpesviruses. We have detected transcripts for both UL33 and M33 as early as 3 or 4 h postinfection, and these reappear at late times. In addition, we have identified N-terminal splicing for both the UL33 and M33 RNA transcripts. For both open reading frames, splicing results in the introduction of amino acids which are highly conserved among known GCRs. To characterise the function of the M33 in the natural host, two independent MCMV recombinant viruses were prepared, each of which possesses an M33 open reading frame which has been disrupted with the beta-galactosidase gene. While the recombinant M33 null viruses showed no phenotypic differences in replication from wild-type MCMV in primary mouse embryo fibroblasts in vitro, they showed severely restricted growth in the salivary glands of infected mice. These data suggest that M33 plays an important role in vivo, in particular in the dissemination to or replication in the salivary gland, and provide the first evidence for the function of a viral GCR homolog in vivo.

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Purpose of review To perform an update review on thyroglobulin gene mutations associated with congenital hypothyroidism, thyroid cancer, and autoimmunity. Recent findings Forty-two thyroglobulin mutations have been identified in dyshormonogenetic congenital hypothyroidism. Clinical and laboratory criteria defining defective thyroglobulin synthesis are mostly related to thyroglobulin mutations, generally caused by intracellular thyroglobulin transport defects to the colloid rather than defects in thyroid hormones synthesis. Some mutated thyroglobulin may escape the rigorous chaperone control and reach the colloid, allowing a wide phenotypic spectrum that includes euthyroidism in an adequate iodine environment. In some patients, continuous levothyroxine treatment does not reduce elevated serum thyroid-stimulating hormone (TSH) levels that may lead to goiter development. Prenatally, inactive mutant thyroglobulin will not be able to synthesize thyroid hormones and may increase pituitary thyrotroph threshold for thyroid hormone feedback. Congenital goiter is a risk factor for thyroid cancer and some thyroglobulin variants may confer susceptibility to thyroid autoimmunity. Summary Advances in the understanding of thyroglobulin genetic defects and its severity should allow researchers to perform adequate molecular diagnosis, genetic counseling, and intrauterine treatment to prevent subtle deficits in central nervous system development. This knowledge should improve the understanding of physiological functions of the thyroid and influence of nutritional iodine.

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The olfactory nervous system is responsible for the detection of odors. Primary sensory olfactory neurons are located in a neuroepithelial sheet lining the nasal cavity. The axons from these neurons converge on to discrete loci or glomeruli in the olfactory bulb. Each glomerulus consists of the termination of thousands of primary axons on the dendrites of second-order olfactory neurons. What are the molecular mechanisms which guide growing olfactory axons to select sites in the olfactory bulb? We have shown that subpopulations of these axons differentially express cell surface carbohydrates and that these different subpopulations target and terminate in particular regions of the olfactory bulb. Interestingly, the olfactory neurons and glial components in the olfactory pathway between the nose and brain express galectin-1. By using in vitro assays of neurite outgrowth we found that both galectin-1 and it's ligands were capable of specifically stimulating neurite elongation. Examination of the olfactory system in galectin-1 null mutants revealed that a subpopulation of axons failed to navigate to their target site in the olfactory bulb. This is the first phenotypic effect observed in galectin-1 null mutants and indicates that galectin-1 has a role in the growth and/or guidance of a subpopulation of axons in the olfactory system during development.

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The budding bacterium Blastobacter natatorius belongs to the alpha-4 group of the Proteobacteria and clusters phylogenetically on a deep branch with Sphingomonas capsulata, with which it shares 93.9% 16S rRNA sequence similarity. On phylogenetic, phenotypic, and chemotaxonomic grounds a proposal is made to transfer B. natatorius to the genus Blastomonas gen, nov. as Blastomonas natatoria comb, nov.

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In the development of atherosclerotic lesions, three basic processes occur: 1) invasion of the artery wall by leucocytes, particularly monocytes and T-lymphocytes; 2) smooth muscle phenotypic modulation, proliferation, and synthesis of extracellular matrix; and 3) intracellular (macrophage and smooth muscle) lipoprotein uptake and lipid accumulation. Invasion of the vessel wall by leucocytes is mediated through the expression of adhesion molecules on both leucocytes and the endothelium making them 'sticky'. The adhesion molecules are induced by high serum cholesterol levels or complement fragments. Leucocytes which have adhered to the endothelium are chemo-attracted into the vessel wall by cytokines produced by early arriving leucocytes or by low density lipoprotein which has passively passed into the wall, in the process being trapped and oxidised. The oxidised low density lipoprotein is taken up by scavenger receptors (which are not subject to down-regulation) on both macrophages and smooth muscle cells. The overaccumulation of lipid is toxic to the cells and they die contributing to the central necrotic core. The macrophages and T-lymphocytes produce substances which induce smooth muscle cells of the artery wall to change from a 'contractile' (high volume fraction of myofilaments [V(v)myo]) to a 'synthetic' (low V(v)myo) phenotype. In this altered state they respond to growth factors released from macrophages, platelets, regenerating endothelial cells and smooth muscle cells; produce large amounts of matrix; express lipoprotein scavenger receptors; express adhesion molecules for leucocytes; and express HLA-DR following exposure to the T-lymphocyte product, IFN-delta, suggesting that they can become involved in a generalised immune reaction.

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Introduction. Marked intolerance or intrusive re-experiencing of ordinary sensory stimuli that in turn drive functionally impairing compulsive behaviors are occasionally seen in voting children with OCD. Methods. We describe a number of children with DSM-IV OCD ascertained from of family genetic study of pediatric OCD, whose intolerance: of ordinary sensory stimuli created significant subjective distress and time-consuming ritualistic behavior that was clinically impairing. Results. In each case these sensory symptoms were the primary presenting symptoms and were experienced in the absence of intrusive thoughts, images, or ideas associated with ""conventional"" OCD symptoms. Conclusions. These symptoms suggest abnormalities in sensory processing and integration in at least a subset of OCD patients. Recognition of these sensory symptoms and sensory-driven behaviors as part of the broad phenotypic Variation in children with OCD could help clinicians more easily identify OCD patients and,facilitate treatment.

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Introduction: A variety of subjective experiences have been reported to be associated with the symptom expression of obsessive-compulsive disorder (OCD) and Tourette syndrome (TS). First described in TS patients, these subjective experiences have been defined in different ways. There is no consensus in the literature on how to best define subjective experiences. This lack of consensus may hinder the understanding of study results and prevents the possibility of including them in the search for etiological factors associated with OCD and TS. Methods: The objective of this article was to review the descriptions of subjective experiences in the English-language literature from 1980-2007. This meta-analytic review was carried out using the English-language literature from 1980-2007 available on MEDLINE, PsycINFO, and the Cochrane Library databases using the following search terms: premonitory urges, sensory tics, ""just-right"" perceptions, sensory phenomena, sensory experiences, incompleteness, ""not just-right"" phenomena, obsessive-compulsive disorder and TS, including OCD and/or TS, in all combination searches. We also searched for the references cited in each article previously found that referred to the aforementioned terms. Thirty-one articles were included in the study. Results: Subjective experiences, in particular, the sensory phenomena, were important phenotypic variables in the characterization of the tic-related OCD subtype and were more frequent in the early-onset OCD subtype. There is a paucity of studies using structured interviews to assess sensory phenomena, their epidemiology and the etiological mechanisms associated with sensory phenomena. Conclusion: The current review provides some evidence that sensory phenomena can be useful to identify more homogenous subgroups of OCD and TS patients and should be included as important phenotypic variables in future clinical, genetic, neuroimaging, and treatment-response studies.

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Objective: Only few large families with multiple endocrine neoplasia type 1 (MEN1) have been documented. Here, we aimed to investigate the clinical features of a seven-generation Brazilian pedigree. which included 715 at-risk family members. Design: Genealogical and geographic analysis was used to identify the MEN1 pedigree. Clinical and genetic approach was applied to characterize the phenotypic and genotypic features of the family members. Results: Our genetic data indicated that a founding mutation in the MEN1 gene has occurred in this extended Brazilian family. Fifty family members were diagnosed with MEN1. Very high frequencies of functioning and non-functioning MEN1-related tumors were documented and the prevalence of prolactinoma (29.6%) was similar to that previously described in prolactinoma-variant Burin (32%). In addition, bone mineral density analysis revealed severe osteoporosis (T,-2.87 +/- 0.32) of compact bone (distal radius) in hyperparathyroidism (HPT)/MEN1 patients. while marked bone mineral loss in the lumbar spine (T,-1.95 +/- 0.39). with most cancellous bone, and femoral neck (mixed composition: T,-1.48 +/- 0.27) were also present. Conclusions: In this study, we described clinically and genetically the fifth largest MEN1 family in the literature. Our data confirm previous findings suggesting that prevalence of MEN1-related tumors in large families may differ from reports combining cumulative data of small families. Furthermore. we were able to evaluate the bone status in HPT/MEN1 cases, a subject that has been incompletely approached in the literature. We discussed the bone loss pattern found in our MEN1 patients comparing with that of patients with sporadic primary HPT.

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We present a 20-year follow-up on a patient with a ring chromosome 14. The ring chromosome was studied by fluorescence in-situ hybridization (FISH), multiplex-ligation probe amplification (MLPA), and genome wide SNP array, and no deletions of chromosome 14 were detected, although the telomeric repeat sequence was absent from the ring chromosome. The patient had skeletal abnormalities, and susceptibility to infections, as well as seizures and retinal pigmentation, which are commonly found in individuals with a ring 14. Our patient corroborates the idea that even when no genes are lost during ring formation, a complete ring chromosome can produce phenotypic alterations, which presumably result from ring instability or gene silencing due to the new chromosomal architecture. (C) 2010 Wiley-Liss, Inc.

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Background: Recurrent 15q13.3 microdeletions were recently identified with identical proximal (BP4) and distal (BP5) breakpoints and associated with mild to moderate mental retardation and epilepsy. Methods: To assess further the clinical implications of this novel 15q13.3 microdeletion syndrome, 18 new probands with a deletion were molecularly and clinically characterised. In addition, we evaluated the characteristics of a family with a more proximal deletion between BP3 and BP4. Finally, four patients with a duplication in the BP3-BP4-BP5 region were included in this study to ascertain the clinical significance of duplications in this region. Results: The 15q13.3 microdeletion in our series was associated with a highly variable intra-and inter-familial phenotype. At least 11 of the 18 deletions identified were inherited. Moreover, 7 of 10 siblings from four different families also had this deletion: one had a mild developmental delay, four had only learning problems during childhood, but functioned well in daily life as adults, whereas the other two had no learning problems at all. In contrast to previous findings, seizures were not a common feature in our series (only 2 of 17 living probands). Three patients with deletions had cardiac defects and deletion of the KLF13 gene, located in the critical region, may contribute to these abnormalities. The limited data from the single family with the more proximal BP3-BP4 deletion suggest this deletion may have little clinical significance. Patients with duplications of the BP3-BP4-BP5 region did not share a recognisable phenotype, but psychiatric disease was noted in 2 of 4 patients. Conclusions: Overall, our findings broaden the phenotypic spectrum associated with 15q13.3 deletions and suggest that, in some individuals, deletion of 15q13.3 is not sufficient to cause disease. The existence of microdeletion syndromes, associated with an unpredictable and variable phenotypic outcome, will pose the clinician with diagnostic difficulties and challenge the commonly used paradigm in the diagnostic setting that aberrations inherited from a phenotypically normal parent are usually without clinical consequences.

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Background: Germ-line mutations in CYLD are found in patients with familial skin appendage tumours. The protein product functions as a deubiquitinase enzyme, which negatively regulates NF-kappa B and c-Jun N-terminal kinase signalling. Brooke-Spiegler syndrome (BSS) is characterised by cylindromas, trichoepitheliomas and spiradenomas, whereas in familial cylindromatosis (FC) patients present with cylindromas and in multiple familial trichoepitheliomas (MFT) with trichoepitheliomas as the only skin tumour type. Although described as distinct entities, recent studies suggest that they are within the spectrum of a single entity. Objective: To investigate the mutation spectrum of CYLD and possible genotype-phenotype correlations. Methods: 25 families including 13 BSS, 3 FC, and 9 MFT families were examined and evaluated for mutations in the CYLD gene. Results: In total, 18 mutations in CYLD, including 6 novel mutations, were identified in 25 probands (72%). The mutation frequencies among distinct phenotypes were 85% for BSS, 100% for FC, and 44% for MFT. The majority of the mutations were insertions, deletions or nonsense mutations leading to formation of truncated proteins. All mutations were located between exons 9 to 20, encoding the NEMO binding site and the catalytic domain. Genotype-phenotype analysis failed to reveal a correlation between the types of mutations and their location within the gene and the patients` phenotypes and disease severity. Conclusions: This study provides further evidence on the role of CYLD in the pathogenesis of skin appendage tumours characterised by cylindromas, trichoepitheliomas and/or spiradenomas, but the molecular mechanisms of CYLD in skin tumorigenesis and the reasons for phenotypic variability remain to be explored.