What is known as “alternative splicing” has been found to be particularly common in human genes. Up to 94 percent has been found. This is way up from 10 years ago, when it was estimated between 10-50 percent. Even people’s brains often differ in their expression of alternative spliced mRNA isoforms.
“Human genes typically contain several “exons,” or DNA sequences that code for amino acids, the building blocks of proteins. A single gene can produce multiple protein sequences, depending on which exons are included in the mRNA transcript, which carries instructions to the cell’s protein-building machinery.
Two different forms of the same protein, known as isoforms, can have different, even completely opposite functions. For example, one protein may activate cell death pathways while its close relative promotes cell survival.” Science Daily
Medical research conducted like this one normally is a pleasure to read, because it’s approaches it’s research with good old traditional science.
“The researchers found that the type of isoform produced is often highly tissue-dependent. Certain protein isoforms that are common in heart tissue, for example, might be very rare in brain tissue, so that the alternative exon functions like a molecular switch.
Scientists who study splicing have a general idea of how tissue-specificity may be achieved, but they have much less understanding of why isoforms display such tissue specificity, Burge said.”
There is a question in which this article overlooked. Why is alternative splicing at such a high rate needed in the first place? If I were doing this type of research, that would be one of the questions I would be searching for some answers. To my understanding, scientists didn’t think alternative splicing played such a significant role in the human body as it does now.
No doubt, this is something they should look into further as well as trying to understand why isoforms display such specificity in the first place. It’s also very important in understanding how improper sliced genes can help cause diseases.
Complexity of the body is just mind blogging. I think it’s very interesting and we only just have scratched the surface of God’s design. There is so much more out there we can learn, and discover. And studying alternative splicing is one of many.