A dysfunctional Eustachian tube that is always open is called a patulous Eustachian tube. Patients with this rare condition are plagued by chronic ear infections. A much more common problem is a failure of the Eustachian tube to effectively regulate air pressure.
A frameshift mutation (also called a framing error or a reading frame shift) is a genetic mutation caused by indels (insertions or deletions) of a number of nucleotides in a DNA sequence that is not divisible by three.he frameshift mutation will also alter the first stop codon (UAA, UGA or UAG) encountered in the sequence. The polypeptide being created could be abnormally short or abnormally long, and will most likely not be functional.
Insertion or deletion of a single letter can sometimes cause a frameshift mutation, in which the entire amino acid sequence of the resulting protein is changed. Gene or Region Duplication. Sometimes errors during DNA replication can duplicate an entire gene or region of a genome. This type of error can cause more of a protein to be produced, because after duplication, there are two genes that encode it rather than one.