Whole-genome sequencing in patients with ciliopathies uncovers a novel recurrent tandem duplication in IFT140.
Hum Mutat
; 39(7): 983-992, 2018 07.
Article
in En
| MEDLINE
| ID: mdl-29688594
ABSTRACT
Ciliopathies represent a wide spectrum of rare diseases with overlapping phenotypes and a high genetic heterogeneity. Among those, IFT140 is implicated in a variety of phenotypes ranging from isolated retinis pigmentosa to more syndromic cases. Using whole-genome sequencing in patients with uncharacterized ciliopathies, we identified a novel recurrent tandem duplication of exon 27-30 (6.7 kb) in IFT140, c.3454-488_4182+2588dup p.(Tyr1152_Thr1394dup), missed by whole-exome sequencing. Pathogenicity of the mutation was assessed on the patients' skin fibroblasts. Several hundreds of patients with a ciliopathy phenotype were screened and biallelic mutations were identified in 11 families representing 12 pathogenic variants of which seven are novel. Among those unrelated families especially with a Mainzer-Saldino syndrome, eight carried the same tandem duplication (two at the homozygous state and six at the heterozygous state). In conclusion, we demonstrated the implication of structural variations in IFT140-related diseases expanding its mutation spectrum. We also provide evidences for a unique genomic event mediated by an Alu-Alu recombination occurring on a shared haplotype. We confirm that whole-genome sequencing can be instrumental in the ability to detect structural variants for genomic disorders.
Key words
Full text:
1
Database:
MEDLINE
Main subject:
Carrier Proteins
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Cerebellar Ataxia
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Retinitis Pigmentosa
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Ciliopathies
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Whole Genome Sequencing
Limits:
Female
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Humans
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Male
Language:
En
Year:
2018
Type:
Article