Minigene splicing assays reveal new insights into exonic variants of the
SLC12A3 gene in Gitelman Syndrome.
Abstract
Gitelman syndrome (GS) is a kind of salt-losing tubular disease, most of
which is caused by SLC12A3 gene variants, and missense variants
account for the majority. Recently, the phenomenon of exon skipping, in
which exonic variants disrupt normal pre-mRNA splicing, has been related
to a variety of diseases. The purpose of this study was to identify the
effect of previously presumed missense SLC12A3 variants on
pre-mRNA splicing using bioinformatics tools and minigenes. The results
revealed that, among ten candidate variants, six variants
(c.602G>A, c.602G>T, c.1667C>T,
c.1925G>A, c.2548G>C and
c.2549G>C) led to complete or incomplete exon skipping by
affecting exonic splicing regulatory elements and/or disturbing
canonical splice sites. It is worth mentioning that this is the largest
study on pre-mRNA splicing of SLC12A3 exonic variants. In
addition, our study emphasizes the importance of detecting splicing
function at the mRNA level in GS and indicates that minigene analysis is
a valuable tool for splicing functional assays of variants in
vitro.