Answer to Question #100080 in Genetics for Baha Ahmed

Question

Lamin A codes for a protein required for the structural support of the nuclear envelope in cells. Without a functional protein, the nuclear envelope becomes unstable, eventually damaging the nucleus and causing cells to die. Based on what you learned in this Click & Learn, propose a genetic medicine strategy you could develop to treat patients with progeria. Describe which step in gene expression you might target and why you would target that step, the intervention tool you would use, and explain how this strategy would treat the disease.

Answer 1

Progeria is caused by several point mutations that occur in the LMNA gene. This mutation results in the synthesis of the shorter transcript and, as a result, shorter protein product (progerin) that cannot undergo the detachment of the farnesyl group significantly affecting the protein functioning. The only possible genetic medicine strategy that could be used to treat progeria is gene editing. As mutations are located in the LMNA gene, the use of gene editing approaches (i.e., CRISPR Cas9) could be used to delete the mutation inserting the correct nucleotide sequence. In this case, the gene will be corrected prior to transcription and replication processes. As a result, gene editing would completely remove the mutation resulting in the production of correct protein, whereas daughter cells would receive edited gene sequence. Lentiviruses or adenoviruses could be used to deliver the required sgRNA and Cas9-encoding sequence to various cells in the organism.