Argentine sisters grapple with inherited GRN mutation as mother battles frontotemporal dementia

Eugenia Streb, an Argentine architect and visual artist, received a frontotemporal dementia diagnosis, prompting genetic testing that revealed her daughters Rosa (25) and Carmen (29) are carriers of the same GRN mutation. The gene, located on chromosome 17, controls production of progranulin, and its loss leads to the neurodegenerative disorder. Autosomal dominant inheritance means each child of a carrier faces a 50% chance of inheriting the mutation, with pathogenic variants representing about 5% of all FTD cases and 20% of those with a family history.

The family took part in Alector's phase-3 trial of the drug latozinemab, which was discontinued after missing its primary goal. Parallel research in the Basque Country has identified a unique progranulin mutation shared by several unrelated families, suggesting a common ancestor. While caring for their mother, the sisters confront future decisions about having children and possible pre-implantation genetic diagnosis, all while relying on specialized caregivers to manage daily challenges.