Tensor tympani- The tensor tympani is the larger of the two muscles of the auditory canal, the other being stapedius. The muscle functions to dampen down sounds such as chewing. It arises from the cartilaginous portion of the eustachian tube as well as the adjacent section of the greater wing of the sphenoid bone.
A nonsense mutation in the leptin gene that results in a stop codon and lack of leptin production was first observed in mice in 1950. In the mouse gene, arginine-105 is encoded by CGA and only requires one nucleotide change to create the stop codon TGA.
Mutations in the ALDH18A1 (also called P5CS) gene cause autosomal recessive cutis laxa type 3 (ARCL3), also known as DeBarsy syndrome. Similar to PYCR1, the ALDH18A1 protein is an enzyme involved in the production of proline, an amino acid, which is an important building block of elastin.