rs587777086

Positions:

• chr2-27461793-CG-C

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_015662.3(IFT172):​c.2158delC​(p.Arg720fs) variant causes a frameshift change. The variant allele was found at a frequency of 0.0000142 in 1,614,062 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: 𝑓 0.000026 (0 hom., cov: 30)
  • Exomes 𝑓: 0.000013 (0 hom.)
• Consequence: IFT172 NM_015662.3 frameshift
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5
• Conservation: PhyloP100: 5.33

Genes affected

IFT172 (HGNC:30391): (intraflagellar transport 172) This gene encodes a subunit of the intraflagellar transport subcomplex IFT-B. Subcomplexes IFT-A and IFT-B are necessary for ciliary assembly and maintenance. Mutations in this gene have been associated with skeletal ciliopathies, with or without polydactyly, such as such short-rib thoracic dysplasias 1, 9 or 10. [provided by RefSeq, Mar 2014]

IFT172 (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 2-27461793-CG-C is Pathogenic according to our data. Variant chr2-27461793-CG-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 97032.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr2-27461793-CG-C is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
IFT172	NM_015662.3	c.2158delC	p.Arg720fs	frameshift_variant	21/48	ENST00000260570.8	NP_056477.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
IFT172	ENST00000260570.8	c.2158delC	p.Arg720fs	frameshift_variant	21/48	1	NM_015662.3	ENSP00000260570.3

Frequencies

GnomAD3 genomes AF: 0.0000263 AC: 4 AN: 152178 Hom.: 0 Cov.: 30

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000588

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251346 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135844

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000130 AC: 19 AN: 1461884 Hom.: 0 Cov.: 31 AF XY: 0.0000179 AC XY: 13 AN XY: 727244

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000162

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome AF: 0.0000263 AC: 4 AN: 152178 Hom.: 0 Cov.: 30 AF XY: 0.0000404 AC XY: 3 AN XY: 74334

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000588

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000113

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Short-rib thoracic dysplasia 10 without polydactyly Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Nov 07, 2013

- -

Short-rib thoracic dysplasia 10 with or without polydactyly;C4225342:Retinitis pigmentosa 71 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 30, 2023

This sequence change creates a premature translational stop signal (p.Arg720Valfs*28) in the IFT172 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in IFT172 are known to be pathogenic (PMID: 24140113). This variant is present in population databases (no rsID available, gnomAD 0.0009%). This premature translational stop signal has been observed in individual(s) with short-rib thoracic dysplasia (PMID: 24140113). ClinVar contains an entry for this variant (Variation ID: 97032). For these reasons, this variant has been classified as Pathogenic. -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Revvity Omics, Revvity

Dec 06, 2021

- -

Short-rib thoracic dysplasia 10 with or without polydactyly;C4225342:Retinitis pigmentosa 71;C4310707:Bardet-Biedl syndrome 20 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Feb 04, 2022

- -

Retinitis pigmentosa 71 Pathogenic:1

Likely pathogenic, criteria provided, single submitter

research

Ocular Genomics Institute, Massachusetts Eye and Ear

Apr 08, 2021

The IFT172 c.2158del variant was identified in an individual with retinitis pigmentosa with a presumed recessive inheritance pattern. Through a review of available evidence we were able to apply the following criteria: PVS1, PM2. Based on this evidence we have classified this variant as Likely Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs587777086; hg19: chr2-27684660;