Experimental approaches to study the effects of nucleotide sequence variants on splicing in low-expression genes in clinically accessible tissues

Variants affecting pre-mRNA splicing are an established cause of a wide range of hereditary disorders. Experimental validation of aberrant splicing events play an important role in medical genetics in determining the pathogenicity of such variants. However, a key limitation is often the low expression of the target gene in clinically accessible tissues, which makes direct RNA analysis from patient samples impossible. The present work systematizes experimental approaches developed to assess the effects of variants on splicing under conditions of insufficient target gene expression. Furthermore, the possibilities and limitations of each method are discussed, along with their potential role in determining the pathogenicity of variants in hereditary diseases.

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