Biomedical subjects

Pablo Iruzubieta

Publications and source records attributed to Pablo Iruzubieta.

3 recordsLinked to original sources

PubMed2026

Establishment and characterization of three human pluripotent stem cell lines from patients with spinocerebellar ataxia 27B (SCA27B).

Spinocerebellar ataxia 27B (SCA27B) is a common autosomal dominant cerebellar ataxia caused by an intronic GAA•TTC repeat expansion in the FGF14 gene. Here, we report the generation and validation of three human induced pluripotent stem cell (iPSC) lines derived from unrelated individuals with SCA27B, including two lines carrying a monoallelic pathogenic GAA•TTC repeat expansion in FGF14 and one line with biallelic expansions. These iPSC lines constitute a valuable resource, particularly given the predominantly neuronal expression of FGF14, and enable the investigation of disease mechanisms in relevant cell types following neuronal differentiation.

Humans↗

PubMed2026

Establishment and characterization of two human pluripotent stem cell lines from patients with ATX-FGF14/spinocerebellar ataxia 27A (SCA27A).

Spinocerebellar ataxia 27A (SCA27A) is a rare inherited ataxia arising from heterozygous pathogenic loss-of-function variants in FGF14. Autosomal recessive FGF14-related cerebellar ataxia has also been reported in a single individual to date. Here, we describe the generation and characterization of human induced pluripotent stem cell (iPSC) lines derived from two individuals with FGF14-related ataxia (ATX-FGF14): one with SCA27A and one with autosomal recessive disease. Given the predominantly neuronal expression of FGF14, these iPSC lines represent a valuable resource for investigating the cellular and molecular consequences of FGF14 deficiency in disease-relevant neuronal populations following directed differentiation.

Humans↗

PubMed2025

Delineating the pathogenic threshold and phenotypic spectrum of SCA27B: findings from a large French-Canadian cohort.

BACKGROUND: Autosomal dominant spinocerebellar ataxia 27B (SCA27B), caused by an intronic (GAA•TTC) repeat expansion in FGF14, is a common cause of late-onset cerebellar ataxia, but its genotypic and phenotypic spectrum remains to be fully established. METHODS: We analysed the FGF14 (GAA•TTC) repeat expansion in a cohort of 134 patients with ataxia and 822 controls from Quebec. We conducted segregation study in large families to further characterize intergenerational repeat instability. RESULTS: We found a significant enrichment of (GAA•TTC)≥200 alleles in the ataxia cohort compared to controls (53.0%, 71/134, vs 3.6%, 30/822, p < 0.0001), including for (GAA•TTC)200-249 alleles (8.2% vs 2.6%, p = 0.0026). We identified 12 ataxic patients with a phenotype compatible with SCA27B carrying a (GAA•TTC)200-249 expansion supporting the pathogenicity of these alleles in some patients. We further delineated the phenotype of 125 symptomatic individuals from 69 families who carried an FGF14 (GAA•TTC)≥200 repeat expansion. Patients with (GAA•TTC)200-249, (GAA•TTC)250-299, and (GAA•TTC)≥300 had a similar phenotype. We observed that 14% of patients with episodic symptoms (13/92) had severe episodes that were initially misdiagnosed as stroke, vestibular neuritis, Wernicke's encephalopathy, or seizures. DISCUSSION AND CONCLUSION: This large cohort demonstrates that (GAA•TTC)200-249 alleles are enriched in patients with ataxia compared to controls and can be pathogenic for SCA27B, supporting the need to define a lower pathogenic threshold in the presence of specific clinical criteria.

Humans↗