CRISPR-mediated base editing of the Irish Infantile Tay-Sachs mutation

Authors

• M Hernandez
• T Lee
• C Byrnes
• A Crowell
• RL Proia
• CJ Tifft

Abstract

Infantile Tay-Sachs Disease (TSD) is a rare lysosomal storage disorder (LSD) caused by biallelic mutations in HEXA encoding the alpha subunit of a heterodimeric enzyme essential for the breakdown of GM2 ganglioside in lysosomes. One hundred and seventy-one reported pathogenic mutations cause decreased or absent HexA enzyme activity resulting in the accumulation of GM2 ganglioside in neurons of the central nervous system. This accumulation leads to impairment of lysosomal function and neuronal cell death. Infantile TSD has onset of symptoms within the first 6 months of life including hypotonia and cherry red maculae, plateauing then loss of developmental milestones, seizures, and death between 5 to 7 years of age.

While the high prevalence of mutations causing infantile TSD in the Ashkenazi Jewish population has long been recognized, the IVS9+1G>A base change in intron 9 of HEXA is more prevalent in Irish populations, with an estimated carrier frequency of 1 in 50 individuals of Irish descent. The aim of this project is to demonstrate successful CRISPR-mediated base editing of the IVS9+1G>A mutation in primary human fibroblasts of affected patients. On-target editing will be confirmed by DNA and RNA extraction, and successfully edited fibroblasts will be assayed for increased HexA enzyme activity. Once we have successfully shown base-editing in vitro, we will move to in vivo editing in a humanized mouse model carrying the mutation in intron 9 with the goal of developing gene-editing for TSD patients carrying this mutation.

Scientific Focus Area: Genetics and Genomics

This page was last updated on Tuesday, August 6, 2024