A Homozygous PTRHD1 Missense Variant (p.Arg122Gln) in an Individual with Intellectual Disability, Generalized Epilepsy, and Juvenile Parkinsonism

Abstract

Biallelic variants in PTRHD1 have been associated with autosomal recessive intellectual disability, spasticity, and juvenile parkinsonism, with few reported cases. Here, we present the clinical and genetic findings of a female of Austrian origin exhibiting infantile neurodevelopmental abnormalities, intellectual disability, and childhood-onset parkinsonian features, consistent with the established phenotypic spectrum. Notably, she developed genetic generalized epilepsy at age 4, persisting into adulthood. Using diagnostic exome sequencing, we identified a homozygous missense variant (c.365G > A, p.(Arg122Gln)) in PTRHD1 (NM_001013663). In summary, our findings not only support the existing link between biallelic PTRHD1 variants and parkinsonism with neurodevelopmental abnormalities but also suggest a potential extension of the phenotypic spectrum to include generalized epilepsy.

Keywords

PTRHD1 - parkinsonism - intellectual disability - epilepsy

Ethical Compliance Statement

The authors confirm that no approval of the institutional review board was necessary. An informed consent was given by the patient's mother (legal caregiver). We have read the journal's position on issues involved in ethical publication and affirm that this work is consistent with those guidelines.

Financial Disclosures for the Previous 12 Months

The authors declare that there are no additional disclosures to report.

Publication History

Received: 26 August 2023

Accepted: 14 December 2023

Accepted Manuscript online:
29 January 2024

Article published online:
14 February 2024

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