Rare IFT140-Associated Phenotype of Cranioectodermal Dysplasia and Features of Diagnostic Journey in Patients with Suspected Ciliopathies
BRIEF DESCRIPTION
"A publication broke ground in early 2022, suggesting that loss-of-function variants in IFT140 were associated with Autosomal Dominant Polycystic Kidney Disease (ADPKD) (Senum, 2022). Months later, another publication confirmed this association (Chang, 2022). Unlike the most common causes of ADPKD (PKD1, PKD2), those with ADPKD-IFT140 tend to have fewer kidney and liver cysts and better kidney function over a longer period of time, meaning they are less likely to require dialysis and transplant."
"Prior to this, IFT140 was only associated with two recessive conditions: Short-Rib Thoracic Dysplasia (SRTD9) and non-syndromic Retinitis Pigmentosa (RP80). SRTD9 is characterized by progressive kidney disease, bone abnormalities (like constricted ribcage or polydactyly), and vision loss. Interestingly, some individuals have been reported with cystic kidney disease, an observation also seen in knockout mouse models. Perhaps it was these observations that made researchers query IFT140 in various ADPKD databases." (source, https://perspectives.nsgc.org/Article/ift140-new-horizons-in-cystic-kidney-disease)
IN THE NEWS
Nonsyndromic Retinal Dystrophy due to Bi-Allelic Mutations in the Ciliary Transport Gene IFT140
Sarah Hull, Nicholas Owen, Farrah Islam, Dhani Tracey-White, Vincent Plagnol, Graham E. Holder, Michel Michaelides, Keren Carss; F. Lucy Raymond, Jean-Michel Rozet, Simon C. Ramsden, Graeme C. M. Black, Isabelle Perrault, Ajoy Sarkar, Mariya Moosajee, Andrew R. Webster, Gavin Arno, Anthony T. Moore | Investigative Ophthalmology & Visual Science | March 2016 | Vol.57 | 1053-1062 | doi.org/10.1167/iovs | 15-17976
Mutations in human IFT140 cause non-syndromic retinal degeneration
Mingchu Xu, Lizhu Yang, Feng Wang, Huajin Li,3 Xia Wang, Weichen Wang, Zhongqi Ge, Keqing Wang, Li Zhao, Hui Li, Yumei Li, Ruifang Sui, and Rui Chen | Human Genetics | 28 July 2015 | Vol 134 | 1069–1078 | ncbi.nlm.nih.gov/pmc/articles/PMC4565766/
Purpose: Mutations in the ciliary transporter gene IFT140, usually associated with a severe syndromic ciliopathy, may also cause isolated retinal dystrophy. A series of patients with nonsyndromic retinitis pigmentosa (RP) due to IFT140 was investigated in this study.
Conclusions: This study highlights the phenotype of nonsyndromic RP due to mutations in IFT140 with milder retinal dystrophy than that associated with the syndromic disease.
In this study, we totally investigated seven unrelated non-syndromic RD patients, including five RP and two LCA cases. Among them, five of them are Han Chinese and the remaining two are of European ethnicity diagnosed in United States. The index case we investigated, SRF71, is a 43-year-old male RP patient of Han Chinese ethnicity. . .
Preliminary screening by retinal capture sequencing found no causative mutations in known RP-causing genes. WES data show that he has biallelic variants in IFT140, . . .
Compound heterozygous variants in IFT140 as a cause of non-syndromic Retinitis Pigmentosa
Tisiana Low, Anastassios Kostakis, Meena Balasubramanian | Ophthalmic Genetics | Vol 39 (2) | 286-287 | ISSN 1381-6810
Retinitis pigmentosa (RP) refers to a group of inherited disorders that affect the retina’s ability to respond to light, leading to progressive visual loss. Retinitis pigmentosa sine pigmento is a variant of RP in which there is an absence of characteristic peripheral bone-spicule like pigmentary changes. One of the genes found to be responsible for RP is IFT140, a ciliary transporter gene (OMIM *614620). Homozygous and compound heterozygous IFT140 . . .