Browsing by Author "Micule, Ieva"
Now showing 1 - 6 of 6
Results Per Page
Sort Options
Item Genetic variation spectrum in ATP7B gene identified in Latvian patients with Wilson disease(2017-07) Zarina, Agnese; Tolmane, Ieva; Kreile, Madara; Chernushenko, Aleksandrs; Cernevska, Gunta; Pukite, Ieva; Micule, Ieva; Krumina, Zita; Krumina, Astrida; Rozentale, Baiba; Piekuse, Linda; Scientific Laboratory of Molecular GeneticsBackground: Wilson disease (WD) is an autosomal recessive disorder of copper metabolism caused by allelic variants in ATP7B gene. More than 500 distinct variants have been reported, the most common WD causing allelic variant in the patients from Central, Eastern, and Northern Europe is H1069Q. Methods: All Latvian patients with clinically confirmed WD were screened for the most common mutation p.H1069Q by PCR Bi-PASA method. Direct DNA sequencing of gene ATP7B (all 21 exons) was performed for the patients with WD symptoms, being either heterozygous for H1069Q or without it on any allele. Results: We identified 15 different allelic variants along with eight non-disease-causing allelic variants. Based on the gene molecular analysis and patients' clinical data variant p.His1069Gln was found in 66.9% of WD alleles. Wide clinical variability was observed among individuals with the same ATP7B genotype. The results of our study confirm that neurological manifestations of WD are typically present later than the liver disease but no significant association between the presence/absence of the most common genetic variant and mode of initial WD presentation or age at presentation was identified. Conclusions: (1) The most prevalent mutation in Latvian patients with Wilson disease was c.3207C>A (p.His1069Gln); (2) No significant phenotype–genotype correlation was found in Latvian patients with Wilson disease; (3) The estimated prevalence of Wilson disease in Latvia is 1 of 24,000 cases which is higher than frequently quoted prevalence of 1: 30,000.Item The most common European HINT1 neuropathy variant phenotype and its case studies(2023) Rozevska, Marija; Rots, Dmitrijs; Gailite, Linda; Linde, Ronalds; Mironovs, Stanislavs; Timcenko, Maksims; Linovs, Viktors; Locmele, Dzintra; Micule, Ieva; Lace, Baiba; Kenina, Viktorija; Scientific Laboratory of Molecular GeneticsHINT1 is an ubiquitous homodimeric purine phosphoramidase belonging to the histidine-triad superfamily. In neurons, HINT1 stabilizes the interaction of different receptors and regulates the effects of their signaling disturbances. Changes in HINT1 gene are associated with autosomal recessive axonal neuropathy with neuromyotonia. Aim of the study was detailed description of patients' phenotype with HINT1 homozygous NM_005340.7: c.110G>C (p.Arg37Pro) variant. Seven homozygous and three compound heterozygous patients were recruited and evaluated using standardized tests for CMT patients, in four patients' nerve ultrasonography was performed. The median age of symptom onset was 10 years (range 1–20), with initial complaints being distal lower limb weakness with gait impairment, combined with muscle stiffness, more pronounced in the hands than in the legs and worsened by cold. Arm muscles became involved later, presenting with distal weakness and hypotrophy. Neuromyotonia was present in all reported patients and is thus a diagnostic hallmark. Electrophysiological studies demonstrated axonal polyneuropathy. Impaired mental performance was observed in six out of ten cases. In all patients with HINT1 neuropathy, ultrasound examination showed significantly reduced muscle volume as well as spontaneous fasciculations and fibrillations. The nerve cross-sectional areas of the median and ulnar nerves were closer to the lower limits of the normal values. None of the investigated nerves had structural changes. Our findings broaden the phenotype of HINT1-neuropathy and have implications for diagnostics and ultrasonographic evaluation of HINT1-neuropathy patients.Item New-Born Screening for Spinal Muscular Atrophy : Results of a Latvian Pilot Study(2022-03) Gailite, Linda; Sterna, Olga; Konika, Maija; Isakovs, Aleksejs; Isakova, Jekaterina; Micule, Ieva; Setlere, Signe; Diriks, Mikus; Auzenbaha, Madara; Scientific Laboratory of Molecular GeneticsNew disease-modifying treatments have recently been approved for 5q spinal muscular atrophy (SMA) and early treatment has been associated with a better clinical outcome. Accordingly, new-born screening (NBS) for SMA should be implemented to ensure early diagnosis of affected individuals. The aim of this study was to determine the feasibility and usefulness of NBS for SMA in Latvia. Between February and November of 2021, 10,411 parents consented to participation in the study. DNA testing for the SMN1 exon 7 homozygous deletion was conducted using qPCR with fluorescent locked nucleic acid primers. In the first month of testing, reporting of results took up to a maximum of 17 days after samples arrived in the laboratory. However, following familiarisation with the procedure, the median report time was reduced to 11 days after birth. Forty cases required samples to be taken again due to poor quality of the isolated DNA transpiring from either the quality of the blood punch or manual mistakes during DNA isolation. The SMN1 exon 7 homozygous deletion was identified in two individuals, which was subsequently confirmed by multiplex ligation-dependent probe amplification. When a NBS sample is taken 48 to 72 h after birth and transported to the laboratory within two working days after collection according to legal requirements, DNA test results can be reported to healthcare professionals before the 12th day of life. Expansion of our SMA 5q NBS procedure to the whole of Latvia is feasible and would facilitate early diagnosis and result in more effective treatment. We strongly advocate that SMA is added to the national Latvia Recommended Uniform Screening Panel.Item A novel frameshift variant in the ADA2 gene of a patient with a neurological phenotype : a case report(2022-12) Lucāne, Zane; Dāvidsone, Zane; Micule, Ieva; Auzenbaha, Madara; Kurjāne, Nataļja; Rīga Stradiņš UniversityBackground Adenosine deaminase 2 (ADA2) deficiency is an inherited autoinflammatory syndrome caused by a defect in the ADA2 gene. Most common manifestations include peripheral vasculopathy, early-onset stroke, immunodeficiency, and haematological manifestations. Patients with pathogenic variants that are more detrimental to ADA2’s enzymatic function (e.g. frameshift) have been reported to be prone to developing hematological phenotype. We report here the case of a 13-year-old Caucasian girl with a novel frameshift variant in the ADA2 gene and a clinical phenotype of early-onset stroke. Case presentation The patient was admitted to hospital with complaints of weakness in her right arm, unilateral facial weakness and speech problems. Her initial laboratory workup was normal; however, magnetic resonance imaging of her brain confirmed acute/subacute ischaemic changes in the posterior limb of the left-sided internal capsule and in the apical part of the thalamus. She also had manifestations of immunodeficiency – recurrent skin infections and otitis, chronic Molluscum contagiosum infection in anamnesis and B cell deficiency with a low level of serum IgA. The patient’s DNA was analysed and two pathogenic variants were identified in the ADA2 gene, confirming a diagnosis of adenosine deaminase 2 (ADA2) deficiency. While one of the variants (c.506G > A (p.Arg169Gln)) has been reported previously, the other one is a novel frameshift variant, namely, c.464del (p.Pro155Hisfs*29). The patient received stroke rehabilitation, which significantly improved her functional state. Tumour necrosis factor inhibitor and methotrexate treatment was commenced, and the patient has remained stable with no further ischaemic events. Conclusions Although rare, ADA2 deficiency should be considered in patients with early-onset stroke, especially with concomitant manifestations of inflammatory features or immunodeficiency. This case report extends the genotypic spectrum of ADA2 deficiency.Item Overview of Neuromuscular Disorder Molecular Diagnostic Experience for the Population of Latvia(2022-06-16) Lace, Baiba; Micule, Ieva; Kenina, Viktorija; Setlere, Signe; Strautmanis, Jurgis; Kazaine, Inese; Taurina, Gita; Murmane, Daiga; Grinfelde, Ieva; Kornejeva, Liene; Krumina, Zita; Sterna, Olga; Radovica-Spalvina, Ilze; Vasiljeva, Inta; Gailite, Linda; Stavusis, Janis; Livcane, Diana; Kidere, Dita; Malniece, Ieva; Inashkina, Inna; Rīga Stradiņš University; Scientific Laboratory of Molecular GeneticsBackground and ObjectivesGenetic testing has become an integral part of health care, allowing the confirmation of thousands of hereditary diseases, including neuromuscular disorders (NMDs). The reported average prevalence of individual inherited NMDs is 3.7-4.99 per 10,000. This number varies greatly in the selected populations after applying population-wide studies. The aim of this study was to evaluate the effect of genetic analysis as the first-tier test in patients with NMD and to calculate the disease prevalence and allelic frequencies for reoccurring genetic variants.MethodsPatients with NMD from Latvia with molecular tests confirming their diagnosis in 2008-2020 were included in this retrospective study.ResultsDiagnosis was confirmed in 153 unique cases of all persons tested. Next-generation sequencing resulted in a detection rate of 37%. Two of the most common childhood-onset NMDs in our population were spinal muscular atrophy and dystrophinopathies, with a birth prevalence of 1.01 per 10,000 newborns and 2.08 per 10,000 (male newborn population), respectively. The calculated point prevalence was 0.079 per 10,000 for facioscapulohumeral muscular dystrophy type 1, 0.078 per 10,000 for limb-girdle muscular dystrophy, 0.073 per 10,000 for nondystrophic congenital myotonia, 0.052 per 10,000 for spinobulbar muscular atrophy, and 0.047 per 10,000 for type 1 myotonic dystrophy.DiscussionDNA diagnostics is a successful approach. The carrier frequencies of the common CAPN3, FKRP, SPG11, and HINT1 gene variants as well as that of the SMN1 gene exon 7 deletion in the population of Latvia are comparable with data from Europe. The carrier frequency of the CLCN1 gene variant c.2680C>T p.(Arg894Ter) is 2.11%, and consequently, congenital myotonia is the most frequent NMD in our population.Item Two Cases of Leigh Syndrome in One Family : Diagnostic Challenges and Clinical Management Experience in Latvia(2021) Katkevica, Arta; Kreile, Madara; Grinfelde, Ieva; Taurina, Gita; Micule, Ieva; Dzivite-Krisane, Iveta; Smite-Laguna, Arta; Malniece, Ieva; Rīga Stradiņš UniversityLeigh syndrome is a neurodegenerative disorder with an incidence of 1: 40,000 live births. The clinical presentation of LS is highly variable with heterogeneity in the disease-associated symptoms of cerebellar, motor, and extrapyramidal dysfunction and common infections. There is no effective treatment for this condition; as such, the prognosis of this condition is very poor with death occurring within the first few years of life. In this study, we report the first LS case in Latvia with SURF1 pathogenic variants in two siblings. The difficulties encountered establishing a diagnosis for the first proband and the effective prenatal diagnosis for the second offspring that led to termination of the pregnancy are discussed.