What are intronic mutations and why do they make people ill?

We are often contacted by patients with Fabry-related conditions who have intronic mutations in their genetics. Therefore, we would like to turn our and your attention back to intronic mutations:

Intronic mutations are an even broader topic. If you ask the Fabry experts, they usually explain that intronic mutations cannot do anything because there is no information in the introns. The answer is that simple and that wrong.

If you want to read the details and have access to Pubmed: https://pubmed.ncbi.nlm.nih.gov/28497172/ (“Deep intronic mutations and human disease”, direct at Springer: https://link.springer.com/article/10.1007/s00439-017-1809-4, Human Genetics volume 136, pages 1093–1111; 2017)

Briefly and simplified: on the one hand, there is also regulatory information in the introns that has an influence on enzyme production. On the other hand, certain sequences of the DNA sequence are used to determine between the introns and exons. If a new exon start is created by mutation in the intron, then the gene is read incorrectly (even if the “original” exons are all correct).

Unfortunately, most gene tests do not pay attention to intronic mutations at all, these areas are not analysed at all. But at the latest, if lyso-GB3-values or enzyme activity are abnormal, one has to search for the cause, which can then lie in the intron.

See also the article on intronic mutations on our website.