Growth in ataxia telangiectasia

BACKGROUND: Ataxia telangiectasia (A-T) is a DNA repair disorder that affects multiple body systems. Neurological problems and immunodeficiency are two important features of this disease. At this time, two main severity groups are defined in A-T: classic (the more severe form) and mild. Poor growth is a common problem in classic A-T. An objective of this study was to develop growth references for classic A-T. Another objective was to compare growth patterns in classic A-T and mild A-T with each other and with the general population, using the CDC growth references. A final objective was to examine the effects of chronic infection on height. RESULTS: We found that classic A-T patients were smaller overall, and suffered from height and weight faltering that continued throughout childhood and adolescence. When compared to the CDC growth references, the median heights and weights for both male and female patients eventually fell to or below the 3rd centile on the CDC charts. Height faltering was more pronounced in females. Birthweight was lower in the classic A-T group compared to mild A-T and the general population, whereas birth length was not. Finally, we investigated height and BMI faltering in relation to number of infections and found no association. CONCLUSIONS: Classic A-T appears to affect growth in utero. Although children appear to grow well in very early life, faltering begins early, and is unrelenting

Proteomic Characterization of Cerebrospinal Fluid from Ataxia-Telangiectasia (A-T) Patients Using a LC/MS-Based Label-Free Protein Quantification Technology

Cerebrospinal fluid (CSF) has been used for biomarker discovery of neurodegenerative diseases in humans since biological changes in the brain can be seen in this biofluid. Inactivation of A-T-mutated protein (ATM), a multifunctional protein kinase, is responsible for A-T, yet biochemical studies have not succeeded in conclusively identifying the molecular mechanism(s) underlying the neurodegeneration seen in A-T patients or the proteins that can be used as biomarkers for neurologic assessment of A-T or as potential therapeutic targets. In this study, we applied a high-throughput LC/MS-based label-free protein quantification technology to quantitatively characterize the proteins in CSF samples in order to identify differentially expressed proteins that can serve as potential biomarker candidates for A-T. Among 204 identified CSF proteins with high peptide-identification confidence, thirteen showed significant protein expression changes. Bioinformatic analysis revealed that these 13 proteins are either involved in neurodegenerative disorders or cancer. Future molecular and functional characterization of these proteins would provide more insights into the potential therapeutic targets for the treatment of A-T and the biomarkers that can be used to monitor or predict A-T disease progression. Clinical validation studies are required before any of these proteins can be developed into clinically useful biomarkers

Wee1B, Myt1, and Cdc25 function in distinct compartments of the mouse oocyte to control meiotic resumption

Keeping Wee1B in the nucleus is important to maintain meiotic arrest, but its timely export is also required for meiosis to resume

Ataxia telangiectasia: a review

Abstract Definition of the disease Ataxia telangiectasia (A-T) is an autosomal recessive disorder primarily characterized by cerebellar degeneration, telangiectasia, immunodeficiency, cancer susceptibility and radiation sensitivity. A-T is often referred to as a genome instability or DNA damage response syndrome. Epidemiology The world-wide prevalence of A-T is estimated to be between 1 in 40,000 and 1 in 100,000 live births. Clinical description A-T is a complex disorder with substantial variability in the severity of features between affected individuals, and at different ages. Neurological symptoms most often first appear in early childhood when children begin to sit or walk. They have immunological abnormalities including immunoglobulin and antibody deficiencies and lymphopenia. People with A-T have an increased predisposition for cancers, particularly of lymphoid origin. Pulmonary disease and problems with feeding, swallowing and nutrition are common, and there also may be dermatological and endocrine manifestations. Etiology A-T is caused by mutations in the ATM (Ataxia Telangiectasia, Mutated) gene which encodes a protein of the same name. The primary role of the ATM protein is coordination of cellular signaling pathways in response to DNA double strand breaks, oxidative stress and other genotoxic stress. Diagnosis The diagnosis of A-T is usually suspected by the combination of neurologic clinical features (ataxia, abnormal control of eye movement, and postural instability) with one or more of the following which may vary in their appearance: telangiectasia, frequent sinopulmonary infections and specific laboratory abnormalities (e.g. IgA deficiency, lymphopenia especially affecting T lymphocytes and increased alpha-fetoprotein levels). Because certain neurological features may arise later, a diagnosis of A-T should be carefully considered for any ataxic child with an otherwise elusive diagnosis. A diagnosis of A-T can be confirmed by the finding of an absence or deficiency of the ATM protein or its kinase activity in cultured cell lines, and/or identification of the pathological mutations in the ATM gene. Differential diagnosis There are several other neurologic and rare disorders that physicians must consider when diagnosing A-T and that can be confused with A-T. Differentiation of these various disorders is often possible with clinical features and selected laboratory tests, including gene sequencing. Antenatal diagnosis Antenatal diagnosis can be performed if the pathological ATM mutations in that family have been identified in an affected child. In the absence of identifying mutations, antenatal diagnosis can be made by haplotype analysis if an unambiguous diagnosis of the affected child has been made through clinical and laboratory findings and/or ATM protein analysis. Genetic counseling Genetic counseling can help family members of a patient with A-T understand when genetic testing for A-T is feasible, and how the test results should be interpreted. Management and prognosis Treatment of the neurologic problems associated with A-T is symptomatic and supportive, as there are no treatments known to slow or stop the neurodegeneration. However, other manifestations of A-T, e.g. immunodeficiency, pulmonary disease, failure to thrive and diabetes can be treated effectively

Minimum effective betamethasone dosage on the neurological phenotype in patients with Ataxia-Telangiectasia: a multicenter observer-blind study

BACKGROUND AND PURPOSE: Ataxia-Telangiectasia (A-T) is a rare neurodegenerative disease, due to A-T Mutated (ATM) gene mutations, which typically presents with signs of progressive neurological dysfunction, cerebellar ataxia and uncoordinated movements. A-T severely affects patients' quality of life (QoL). Successful treatment options are still not available. Aim of this multicenter study, performed with a blind evaluation procedure, was to define the minimal effective dosage of oral betamethasone, thus preventing the occurrence of side effects. METHODS: Nine A-T patients were enrolled to receive betamethasone at increasing dosages of 0.001, 0.005 and 0.01 mg/kg/day. Neurological assessment and the evaluation of QoL were performed through the Scale for the Assessment and Rating of Ataxia (SARA) and the Italian version of the Children Health Assessment Questionnaire (CHAQ) at each time-point. Drug safety profile was evaluated. Patients were categorized as responders, partial responders and non-responders. RESULTS: Four out 9 patients had a benefit at the dose of 0.005 mg/kg/day of oral betamethasone. Using the higher dosage, only 1 additional patient had a positive response. Conversely, a daily dose of 0.001 mg/kg was ineffective. A correlation between the serum ACTH levels and the clinical response was observed. Five of 30 CHAQ items improved in 4 patients. CONCLUSIONS: These data suggest that a short-term betamethasone oral treatment, at a daily dosage of 0.005 mg/kg, is effective in some patients. Pre-existing risk factors for side-effects should be taken into account before therapy