A very early diagnosis of Alstrӧm syndrome by next generation sequencing.

Background: Alström syndrome is a rare recessively inherited disorder caused by variants in the ALMS1 gene. It is characterized by multiple organ dysfunction, including cone-rod retinal dystrophy, dilated cardiomyopathy, hearing loss, obesity, insulin resistance, hyperinsulinemia, type 2 diabetes mellitus and systemic fibrosis. Heterogeneity and age-dependent development of clinical manifestations make it difficult to obtain a clear diagnosis, especially in pediatric patients.

Treatment outcome of creatine transporter deficiency: international retrospective cohort study.

To evaluate the outcome of current treatment for creatine transporter (CRTR) deficiency, we developed a clinical severity score and initiated an international treatment registry. An online questionnaire was completed by physicians following patients with CRTR deficiency on a treatment, including creatine and/or arginine, and/or glycine. Clinical severity score included 1) global developmental delay/intellectual disability; 2) seizures; 3) behavioural disorder.

De novo exonic mutation in MYH7 gene leading to exon skipping in a patient with early onset muscular weakness and fiber-type disproportion.

Here we report on a case of MYH7-related myopathy in a boy with early onset of muscular weakness and delayed motor development in infancy. His most affected muscles were neck extensors showing a dropped head sign, proximal muscles of lower limbs with positive Gower's sign, and trunk muscles. Brain and spinal cord MRI scans, echocardiography, and laboratory analyses including creatine kinase and lactate did not reveal any abnormalities.

The Frequency of Methylation Abnormalities Among Estonian Patients Selected by Clinical Diagnostic Scoring Systems for Silver-Russell Syndrome and Beckwith-Wiedemann Syndrome.

Aims: To study the frequency of methylation abnormalities among Estonian patients selected according to published clinical diagnostic scoring systems for Silver-Russell syndrome (SRS) and Beckwith-Wiedemann syndrome (BWS).

Materials And Methods: Forty-eight patients with clinical suspicion of SRS (n = 20) or BWS (n = 28) were included in the study group, to whom methylation-specific multiplex ligation-dependant probe amplification analysis of 11p15 region was made. In addition, to patients with minimal diagnostic score for either SRS or BWS, multilocus methylation-specific single nucleotide primer extension assay was performed.

Analysis of NADP+-dependent isocitrate dehydrogenase-1/2 gene mutations in pediatric brain tumors: report of a secondary anaplastic astrocytoma carrying the IDH1 mutation.

Somatic mutations of the isocitrate dehydrogenase-1 gene (IDH1), most commonly resulting in replacement of arginine at position 132 by histidine (p.R132H), have been reported for WHO grade II and III diffuse gliomas and secondary glioblastomas. We investigated IDH1/2 mutations in a retrospective series of 165 pediatric brain tumors, including atypical teratoid/rhabdoid tumors (AT/RT) and choroid plexus tumors, which had not previously been investigated.

The live-birth prevalence of mucopolysaccharidoses in Estonia.

Previous studies on the prevalence of mucopolysaccharidoses (MPS) in different populations have shown considerable variations. There are, however, few data with regard to the prevalence of MPSs in Fenno-Ugric populations or in north-eastern Europe, except for a report about Scandinavian countries. A retrospective epidemiological study of MPSs in Estonia was undertaken, and live-birth prevalence of MPS patients born between 1985 and 2006 was estimated.

Prevalence of c.35delG and p.M34T mutations in the GJB2 gene in Estonia.

Objective: The purpose of this study was to determine the prevalence of c.35delG and p.M34T mutations in the GJB2 gene among children with early onset hearing loss and within a general population of Estonia.

A novel mutation in the SCO2 gene in a neonate with early-onset cardioencephalomyopathy.

Mutations in the SCO2 gene [SCO cytochrome oxidase deficient homolog 2 (yeast)] causing cytochrome c oxidase deficiency have been reported in at least in 26 patients with fatal infantile cardioencephalomyopathy. Mutation 1541G > A affecting protein stability is associated with the majority of cases, and the other 11 described mutations have more serious deleterious structural consequences for the protein product. Reported here is a novel case caused by compound heterozygosity of SCO2.

Splice variant IVS2-2A>G in the SLC26A5 (Prestin) gene in five Estonian families with hearing loss.

Objective: The aim of our study was to identify the IVS2-2A>G sequence change in the SLC26A5 (Prestin) gene in Estonian individuals with hearing loss and in their family members.

Methods: In the years 2005-2007 we have screened 194 probands with early onset hearing loss and 68 family members with an arrayed primer extension (APEX) microarray, which covers 201 mutations in six nuclear genes (GJB2, GJB6, GJB3, GJA1, SLC26A4, SLC26A5) and two mitochondrial genes encoding 12S rRNA and tRNA-Ser (UCN).

Results: In four probands with early onset hearing loss and in five unaffected family members from five families we identified the IVS2-2A>G change in one allele of the SLC26A5 gene.