A high-fidelity CRISPR-Cas13 system improves abnormalities associated with C9ORF72-linked ALS/FTD.

An abnormal expansion of a GGGGCC (GC) hexanucleotide repeat in the C9ORF72 gene is the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), two debilitating neurodegenerative disorders driven in part by gain-of-function mechanisms involving transcribed forms of the repeat expansion. By utilizing a Cas13 variant with reduced collateral effects, we develop here a high-fidelity RNA-targeting CRISPR-based system for C9ORF72-linked ALS/FTD. When delivered to the brain of a transgenic rodent model, this Cas13-based platform curbed the expression of the GC repeat-containing RNA without affecting normal C9ORF72 levels, which in turn decreased the formation of RNA foci, reduced the production of a dipeptide repeat protein, and reversed transcriptional deficits.

A case of papillary thyroid carcinoma in struma ovarii and review of the literature.

Malignancy in struma ovarii is a rare form of ovarian germ cell tumour. Because of its rarity, the diagnosis and management of the tumour have not been clearly defined. We present a case of 67- year-old female with papillary carcinoma arising in struma ovarii and review the literature on malignancy in struma ovarii cases, focusing on management of these cases.