Congenital cytomegalovirus (cCMV) infection is the most common intrauterine infection. A non-specific immune response is the first line of host defense mechanism against human cytomegalovirus (HCMV). There is limited data on associations between Single Nucleotide Polymorphisms (SNPs) in genes involving innate immunity and the risk and clinical manifestation of cCMV infection. The aim of the study was to investigate association between selected SNPs in genes encoding cytokines and cytokine receptors, and predisposition to cCMV infection including symptomatic course of disease and symptoms. A panel of eight SNPs: IL1B rs16944, IL12B rs3212227, IL28B rs12979860, CCL2 rs1024611, DC-SIGN rs735240, TLR2 rs5743708, TLR4 rs4986791, TLR9 rs352140 was analyzed in 233 infants (92 cCMV-infected and 141 healthy controls). Associations between genotyped SNPs and predisposition to cCMV infection and symptoms were analyzed. The association analysis was performed using SNPStats software. No statistically significant association was found between any genotyped SNPs and predisposition to cCMV infection and symptomatic course of disease. In relation to particular symptoms, polymorphism of IL12B rs3212227 was linked to decreased risk of prematurity (OR = 0.37;95%CI,0.14-0.98;p = 0.025), while polymorphism of IL1B rs16944 was linked to reduced risk of splenomegaly (OR = 0.36;95% CI,0.14-0.98; p = 0.034) in infants with cCMV infection. An increased risk of thrombocytopenia was associated with IL28B rs12979860 polymorphism (OR = 2.55;95%CI,1.03-6.32;p = 0.042), while hepatitis was associated with SNP of TLR4rs4986791 (OR = 7.80;95% CI,1.49-40,81; p = 0.024). This is the first study to demonstrate four new associations between SNPs in selected genes (IL1B, IL12B, IL28B, TLR4) and particular symptoms in cCMV disease. Further studies on the role of SNPs in the pathogenesis of cCMV infection and incorporation of selected SNPs in the clinical practice might be considered in the future.

Congenital microcephaly causes smaller than average head circumference relative to age, sex and ethnicity and is most usually associated with a variety of neurodevelopmental disorders. The underlying etiology is highly heterogeneous and can be either environmental or genetic. Disruption of any one of multiple biological processes, such as those underlying neurogenesis, cell cycle and division, DNA repair or transcription regulation, can result in microcephaly. This etiological heterogeneity manifests in a clinical variability and presents a major diagnostic and therapeutic challenge, leaving an unacceptably large proportion of over half of microcephaly patients without molecular diagnosis. To elucidate the clinical and genetic landscapes of congenital microcephaly, we sequenced the exomes of 191 clinically diagnosed patients with microcephaly as one of the features. We established a molecular basis for microcephaly in 71 patients (37%), and detected novel variants in five high confidence candidate genes previously unassociated with this condition. We report a large number of patients with mutations in tubulin-related genes in our cohort as well as higher incidence of pathogenic mutations in MCPH genes. Our study expands the phenotypic and genetic landscape of microcephaly, facilitating differential clinical diagnoses for disorders associated with most commonly disrupted genes in our cohort.

Background: Congenital cytomegalovirus (cCMV) infection of the central nervous system (CNS) can cause ventriculomegaly, gliosis, calcifications and cortical defects. Detection of CMV DNA in cerebrospinal fluid by PCR (CSF-CMV-PCR) is a marker of CNS involvement. Objective: To evaluate a diagnostic value of the positive CSF-CMV-PCR in cCMV. Methods: Analysis of clinical, laboratory, neuroimaging and single-nucleotide polymorphisms (SNPs) data according to the results of CSF-CMV-PCR were performed in infants with cCMV. Results: A total of 168 infants were included; 145 (86.3%) had negative and 23 (13.7%) had positive CSF-CMV-PCR results. Associations between the positive CSF-CMV-PCR results and prematurity (odds ratio [OR] = 3.24; 95% confidence interval [CI]: 1.30–8.07), microcephaly (OR = 5.67; 95% CI: 2.08–15.41), seizures (OR = 4.15; 95% CI: 1.10–15.67), sensorineural hearing loss (OR = 6.6; 95% CI: 2.49–17.46), splenomegaly (OR = 8.13; 95% CI: 3.12–21.16), hepatitis (OR = 10.51; 95% CI: 3.31–33.35), petechiae (OR = 10.21; 95% CI: 3.78–27.57) and heterozygous T/C genotype at TLR4rs4986791 (OR = 7.88; 95% CI: 1.55–40.12) were observed. When using a multivariate logistic regression analysis, only the presence of severe sensorineural hearing loss (OR = 7.18; 95% CI: 1.75–29.34, P = 0.006), cystic lesions on MRI (OR 5.29; 95% CI: 1.31–21.36, P = 0.02), and calcifications on MRI (OR = 7.19; 95% CI: 1.67–30.97, P = 0.008) remained as the significant independent predictors of the positive CSF-CMV-PCR results. Conclusions: The detection of CMV DNA in CSF is associated with a higher rate of CNS damage including abnormal MRI neuroimaging and severe hearing loss. Therefore, detection of CMV DNA in CSF may be considered as a marker of severe CNS injury in cCMV infection. However, the very low prevalence of the positive CSF-CMV-PCR results, even in infants with proven CNS involvement, may imply its limited role in clinical practice.

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