Primary ciliary dyskinesia (PCD) is a rare inherited autosomal recessive or X-linked disorder that mainly affects lungs. Dysfunction of respiratory cilia causes symptoms such as chronic rhinosinusitis, coughing, rhinitis, conductive hearing loss and recurrent lung infections with bronchiectasis. It is now well known that pathogenic genetic changes lead to ciliary dysfunction. Here we report usage of clinical-exome based NGS approach in order to reveal underlying genetic causes in cohort of 21 patient with diagnosis of PCD. By detecting 18 (12 novel) potentially pathogenic genetic variants, we established the genetic cause of 11 (9 unrelated) patients. Genetic variants were detected in six PCD disease-causing genes, as well as in SPAG16 and SPAG17 genes, that were not detected in PCD patients so far, but were related to some symptoms of PCD. The most frequently mutated gene in our cohort was DNAH5 (27.77%). Identified variants were in homozygous, compound heterozygous and trans-heterozygous state. For detailed characterization of one novel homozygous genetic variant in DNAI1 gene (c. 947_948insG, p. Thr318TyrfsTer11), RT-qPCR and Western Blot analysis were performed. Molecular diagnostic approach applied in this study enables analysis of 29 PCD disease-causing and related genes. It resulted in mutation detection rate of 50% and enabled discovery of twelve novel mutations and pointed two possible novel PCD candidate genes.

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IntroductionSarcoidosis is a rare multisystem granulomatous disease with unknown etiology. The interplay of vitamin D deficiency and genetic polymorphisms in genes coding for the proteins relevant for metabolism of vitamin D is an important, but unexplored area. The aim of this study was to investigate the association between single nucleotide polymorphisms (SNPs) in CYP2R1 (rs10741657), CYP27B1 (rs10877012), DBP (rs7041; rs4588), and VDR (rs2228570) genes and sarcoidosis, as well as the association between these SNPs and 25(OH)D levels in sarcoidosis patients.Material and methodsFor that purpose we genotyped 86 sarcoidosis patients and 50 healthy controls using the PCR-RFLP method.ResultsSubjects carrying the CC genotype of CYP27B1 rs10877012 have 10 times lower odds of suffering from sarcoidosis. Moreover, DBP rs4588 AA genotype was shown to be a susceptibility factor, where carriers of this genotype had eight times higher odds for developing sarcoidosis. In addition, the A allele of the DBP gene (rs4588) was associated with lower levels of 25(OH)D in sarcoidosis patients.ConclusionsThese results suggest that patients with vitamin D deficiency should be regularly tested for genetic modifiers that are related to sarcoidosis in order to prevent development of serious forms of sarcoidosis.

Introduction: Maturity onset diabetes of the young (MODY) is a rare form of monogenic diabetes. Being clinically and genetically heterogeneous, it is often misdiagnosed as type 1 or type 2 diabetes, leading to inappropriate therapy. MODY is caused by a single gene mutation. Thirteen genes, defining 13 subtypes, have been identified to cause MODY. A correct diagnosis is important for the right therapy, prognosis, and genetic counselling. Material and methods: Twenty-nine unrelated paediatric patients clinically suspected of having MODY diabetes were analysed using TruSight One panel for next-generation sequencing (NGS) and multiplex ligation-dependent probe amplification (MLPA) assay. Results: In this study we identified variants in MODY genes in 22 out of 29 patients (75.9%). Using two genetic tests, NGS and MLPA, we detected both single nucleotide variants and large deletions in patients. Most of the patients harboured a variant in the GCK gene (11/22), followed by HNF1B (5/22). The rest of the variants were found in the NEUROD1 and HNF1A genes. We identified one novel variant in the GCK gene: c.596T>C, p.Val199Ala. The applied genetic tests excluded the suspected diagnosis of MODY in two patients and revealed variants in other genes possibly associated with the patient's clinical phenotype. Conclusions: In our group of MODY patients most variants were found in the GCK gene, followed by variants in HNF1B, NEUROD1, and HNF1A genes. The combined NGS and MLPA-based genetic tests presented a comprehensive approach for analysing patients with suspected MODY diabetes and provided a successful differential diagnosis of MODY subtypes.

Systemic sclerosis (SSc) is a rare, chronic, multisystem autoimmune disease clinically characterized by progressive fibrosis of the skin and internal organs. The basic mechanism appears to involve endothelial cell injury, overproduction of extracellular matrix proteins, and aberrant immune activation. So far, there have been a few attempts to find genetic biomarkers for monitoring disease activity or for correlation with certain symptoms. In order to reveal reliable biomarkers, we analyzed the expression of four genes representing three important signaling pathways, TLR7, TLR9, and JAK2-STAT3. Using RT-qPCR technique, we analyzed the expression of TLR7, TLR9, JAK2, and STAT3 genes in peripheral blood mononuclear cells of 50 SSc patients and 13 healthy individuals. We detected significant upregulation of TLR7 gene expression in a group of SSc patients compared to non-SSc group. Receiver operating characteristic (ROC) analysis showed that TLR7 expression efficiently discriminates SSc cases from healthy individuals. High TLR7 expression positively correlated with the late form of disease, active SSc, and the presence of digital ulcers. Decreased levels of TLR9 and JAK2 mRNA were found in the patient's cohort in comparison to non-SSc individuals, but showed no correlation with specific clinical outcomes. The expression level of the STAT3 gene did not differ between the analyzed groups. This is the first study on the expression of TLR7, TLR9, and STAT3 genes in SSc patients. Our results show that TLR7, TLR9, and JAK2 genes are potential biomarkers for SSc. The results obtained in this study could contribute to better classification, monitoring, and outcome prediction of patients with SSc based on genetics.