Distal myopathies

Gene: GIPC1

Red List (low evidence)

Comment on list classification: This gene will remain red as it is only the GIPC1_GGC expansion that has been associated with disease.

Created: 10 Aug 2023, 5:16 p.m. | Last Modified: 10 Aug 2023, 5:16 p.m.

Panel Version: 3.12

The GIPC1_GGC expansion has been associated with Oculopharyngodistal myopathy 2 (OMIM:618940), but not with a phenotype in Gen2Phen. PMIDs 32413282 and 33374016 report the 5' UTR GIPC1 expansion in numerous cases of oculopharyngodistal myopathy. No other disease associated GIPC1 variants have been reported to date.

Created: 10 Aug 2023, 5:14 p.m. | Last Modified: 10 Aug 2023, 5:14 p.m.

Panel Version: 3.11

Green List (high evidence)

PMID 33374016: a Chinese cohort of 41 patients with the clinical diagnosis of oculopharyngodistal myopathy (21 cases from seven families and 20 sporadic cases). Overall, the repeat expansion in GIPC1 was identified in 51.9% independent pedigrees (4/7 families and 10/20 sporadic cases). The number of CGG repeats was <30 in controls but >60 in affected individuals. There was a slight correlation between repeat size and the age at onset. Both repeat expansion and retraction were observed during transmission but somatic instability was not evident.

Created: 19 Apr 2021, 8:46 a.m. | Last Modified: 19 Apr 2021, 8:46 a.m.

Panel Version: 1.29

19 families reported with heterozygous trinucleotide repeat expansion in the 5-prime untranslated region and onset of distal muscle weakness, mainly of the lower limbs, and/or ophthalmoplegia in the second or third decades of life. Note this is unlikely to be tractable currently by most NGS assays, and may be best dealt with as an STR disorder here.
Sources: Literature

Created: 17 Jul 2020, midnight

Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted

Phenotypes
Oculopharyngodistal myopathy-2 (OPDM2), MIM#618940

Publications

• 32413282
• 33374016

Mode of pathogenicity
Other