Mutation Analysis of the NRLP3 Gene in Children With Cryopyrin-Associated Fever
No Thumbnail Available
Date
2020
Authors
Auyeryanova, T.
Uakhit, R.
Assylbekova, M.
Mukusheva, Z.
Bayanova, M.
Journal Title
Journal ISSN
Volume Title
Publisher
International conference "MODERN PERSPECTIVES FOR BIOMEDICAL SCIENCES: FROM BENCH TO BEDSIDE”; National Laboratory Astana
Abstract
Introduction: CAPS is a group of severe multi-system, auto-inflammatory diseases with an autosomal
dominant type of inheritance associated with mutations in the cryopyrin NLRP3 gene located on the first
chromosome (1q44). CAPS-syndrome is represented by three phenotypes: familial cold urticarial, Muckle
– Wells syndrome, and CINCA/NOMID syndrome. Today, it is quite a lot known about CAPS-syndrome,
but due to the nonspecific, chronic, remitting course of the disease, diagnosis and, consequently, treatment
of the patient is hindered. The diagnosis is based on the results of molecular genetic approach.
Methods: The DNAs were extracted from the whole blood of patients with suspected periodic fever
(according to the manufacturer’s instructions). The presence or absence of mutations of the NLRP3 gene
were determined by PCR using specific primers followed by purification of amplicons and Sanger sequencing.
Results of Sanger sequencing were analyzed using Seq 6, Sequencher 2.0 software.
Results: The molecular characteristic of the NLRP3 gene includes 10 exons, 32.952base pairs. As of
today, according to the register and database https://infevers.umai-montpellier.fr/web/search.php, 204
mutations of the NLRP3 gene are known, but only 19 mutations are considered pathogenic. Taking into
account that the majority of pathogenic mutations are located in exon 3 of the NLRP3 gene we designed
primers of the 3 exon. After optimizing the primers of 3 exons, we examined 2patients by Sanger sequencing.
Analysis of the electrophoregrams using the Mutation Testing resource revealed a heterozygous
carrier of c. 732G>A (p.Ala 244=; rs3806268) as prediction polymorphism. The frequency of this
polymorphism is high in different populations; the frequency of alleles is about 0.555. The results of
genetic testing allow us to consider the detected variant as the cause of cryopyrin-related syndrome only
if there is sufficient clinical and anamnestic data to confirm the diagnosis.
Conclusion: Thus, this result does not exclude the presence of mutations in other exons, it is necessary
to conduct next generation sequencing of WES. Designing primers were optimized and can use to confirm
diagnosis in molecular genetic tools.
Description
Keywords
auto-inflammatory syndromes, CAPS-syndrome, NLRP3 gene, sequencing, Research Subject Categories::MEDICINE