The Phenotypic Spectrum of Patients with PHARC Syndrome Due to Variants in : An Ophthalmic Perspective

Overview

Journal Genes (Basel)

Publisher MDPI

Date 2021 Sep 28

PMID 34573385

Citations 8

Authors

Xuan-Thanh-An Nguyen

Hind Almushattat

Ine Strubbe

Michalis Georgiou

Catherina H Z Li

Mary J van Schooneveld

Inge Joniau

Elfride De Baere

Ralph J Florijn

Arthur A Bergen

Carel B Hoyng

Michel Michaelides

Bart P Leroy

Camiel J F Boon

Affiliations

Soon will be listed here.

Abstract

This study investigated the phenotypic spectrum of PHARC (polyneuropathy, hearing loss, ataxia, retinitis pigmentosa and early-onset cataract) syndrome caused by biallelic variants in the gene. A total of 15 patients from 12 different families were included, with a mean age of 36.7 years (standard deviation [SD] ± 11.0; range from 17.5 to 53.9) at the most recent examination. The presence and onset of neurological, audiological and ophthalmic symptoms were variable, with no evident order of symptom appearance. The mean best-corrected visual acuity was 1.1 logMAR (SD ± 0.9; range from 0.1 to 2.8; equivalent to 20/250 Snellen) and showed a trend of progressive decline. Different types of cataract were observed in 13 out of 15 patients (87%), which also included congenital forms of cataract. Fundus examination revealed macular involvement in all patients, ranging from alterations of the retinal pigment epithelium to macular atrophy. Intraretinal spicular hyperpigmentation was observed in 7 out of 15 patients (47%). From an ophthalmic perspective, clinical manifestations in patients with PHARC demonstrate variability with regard to their onset and severity. Given the variable nature of PHARC, an early multidisciplinary assessment is recommended to assess disease severity.

Citing Articles

A Novel Compound Heterozygous Variant in the ABHD12 Gene Cause PHARC Syndrome in a Chinese Family: The Proband Presenting New Genotype and Phenotype.

Ma M, Ma J, Lian Y, Wu X, Wang W, Rong W Mol Genet Genomic Med. 2025; 13(2):e70055.

PMID: 39910854 PMC: 11799048. DOI: 10.1002/mgg3.70055.

PHARC syndrome: an overview.

Harutyunyan L, Callaerts P, Vermeer S Orphanet J Rare Dis. 2024; 19(1):416.

PMID: 39501272 PMC: 11539745. DOI: 10.1186/s13023-024-03418-0.

Genotype-phenotype spectrum and correlation of PHARC Syndrome due to pathogenic ABHD12 variants.

Long X, Xiong W, Wang X, Geng J, Zhong M, Huang Y BMC Med Genomics. 2024; 17(1):203.

PMID: 39123271 PMC: 11312174. DOI: 10.1186/s12920-024-01984-7.

Coexistence of Retinitis Pigmentosa and Ataxia in Patients with PHARC, PCARP, and Oliver-McFarlane Syndromes.

Wawrocka A, Walczak-Sztulpa J, Kuszel L, Niedziela-Schwartz Z, Skorczyk-Werner A, Bernardczyk-Meller J Int J Mol Sci. 2024; 25(11).

PMID: 38891946 PMC: 11172263. DOI: 10.3390/ijms25115759.

Unilateral Cataract and Retinitis Pigmentosa in a Patient With Polyneuropathy, Hearing Loss, Ataxia, Retinitis Pigmentosa, and Cataract (PHARC) Syndrome: A Case Report.

E Hernandez-Emanuelli M, Emanuelli A, Izquierdo N Cureus. 2024; 16(2):e54295.

PMID: 38371430 PMC: 10870802. DOI: 10.7759/cureus.54295.

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