Lmna (C1824T). Patients Who Suffer From Hgps Are Mostly
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LMNA (C1824T) Patients who suffer from HGPS are mostly affected by the same single base substitution mutation within the LMNA (C1824T) gene. 90% of these patients suffer from this particular mutation (Prokocimer 2013). A single base substitution mutation is where one "letter" is not copied right and it in turn throws off the entire sequence, which could result in coding different amino acids and also could code to "stop" and form an incomplete protein of which may not function correctly, or at all. This mutation in LMNA (C1824T) is created by abnormal splicing in exon 11. This creates a cryptic splice cite where 50 internal amino acids are deleted (Swahari 2016). The result of this internal deletion of amino acids is the permanent…show more content… Before leaving the nucleus the pre-mRNA may go through a process called RNA splicing (Brooker). During this process the undesirable introns are disposed of while the coding sequences, exons, are spliced together to form messenger RNA (Brooker). Understanding RNA splicing, the most important process that may alter a protein’s shape is alternative splicing (Brooker). This process allows one strand of pre-messenger RNA to produce several different polypeptide sequences (Brooker). One pre-mRNA can create multiple polypeptide sequences which in turn creates proteins that are distinctive from each other. Alternative splicing is seen in the LMNA gene, it produces Lamins A and C (Swahari). Although they are different proteins, they are believed to be functionally redundant (Swahari). During the formation of these proteins a farnesyl group, which embeds into the cell membrane, is added to one end and later the protein is cleaved at a recognition site in exon 11 removing the tip and the farnesyl group (Swahari). Due to the point mutation linked to HGPS 50 amino acids are removed, within these is the recognition site (Swahari). As a result the protein is permanently farnesylated and known as progerin (Swahari). This protein imbeds and accumulates in the cell membrane creating the symptoms of HGPS (Swahari).
All adults and even children produce the protein called progerin. Progerin is a