3-160303973-T-C

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 1P and 1B. PP5BP4

The NM_020800.3(IFT80):​c.1093A>G​(p.Thr365Ala) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000041 in 1,610,068 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T365I) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000024 ( 0 hom. )

Consequence

IFT80
NM_020800.3 missense

Scores

5
10
4

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:7U:1

Conservation

PhyloP100: 7.45

Publications

1 publications found
Variant links:
Genes affected
IFT80 (HGNC:29262): (intraflagellar transport 80) The protein encoded by this gene is part of the intraflagellar transport complex B and is necessary for the function of motile and sensory cilia. Defects in this gene are a cause of asphyxiating thoracic dystrophy 2 (ATD2). Three transcript variants encoding two different isoforms have been found for this gene.[provided by RefSeq, Jun 2010]
TRIM59-IFT80 (HGNC:56756): (TRIM59-IFT80 readthrough (NMD candidate)) This locus represents naturally occurring readthrough transcription between the neighboring TRIM59 (tripartite motif containing 59) and IFT80 (intraflagellar transport 80) genes on chromosome 3. The readthrough transcript is unlikely to produce a protein product. [provided by RefSeq, Jun 2017]

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

PP5
Variant 3-160303973-T-C is Pathogenic according to our data. Variant chr3-160303973-T-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 406217.
BP4
Computational evidence support a benign effect (MetaRNN=0.3552438). . Strength limited to SUPPORTING due to the PP5.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
IFT80NM_020800.3 linkc.1093A>G p.Thr365Ala missense_variant Exon 11 of 20 ENST00000326448.12 NP_065851.1 Q9P2H3-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
IFT80ENST00000326448.12 linkc.1093A>G p.Thr365Ala missense_variant Exon 11 of 20 1 NM_020800.3 ENSP00000312778.7 Q9P2H3-1
TRIM59-IFT80ENST00000483754.1 linkn.1606A>G non_coding_transcript_exon_variant Exon 9 of 19 2 ENSP00000456272.1 H3BRJ5

Frequencies

GnomAD3 genomes
AF:
0.000204
AC:
31
AN:
152220
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000724
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000597
AC:
15
AN:
251088
AF XY:
0.0000442
show subpopulations
Gnomad AFR exome
AF:
0.000926
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000240
AC:
35
AN:
1457730
Hom.:
0
Cov.:
29
AF XY:
0.0000165
AC XY:
12
AN XY:
725510
show subpopulations
African (AFR)
AF:
0.00102
AC:
34
AN:
33376
American (AMR)
AF:
0.00
AC:
0
AN:
44704
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26076
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39486
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86118
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53392
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5740
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1108600
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60238
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.446
Heterozygous variant carriers
0
3
6
8
11
14
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.000203
AC:
31
AN:
152338
Hom.:
0
Cov.:
32
AF XY:
0.000215
AC XY:
16
AN XY:
74504
show subpopulations
African (AFR)
AF:
0.000722
AC:
30
AN:
41580
American (AMR)
AF:
0.0000653
AC:
1
AN:
15306
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5194
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68016
Other (OTH)
AF:
0.00
AC:
0
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.538
Heterozygous variant carriers
0
3
5
8
10
13
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.000116
Hom.:
0
Bravo
AF:
0.000276
ESP6500AA
AF:
0.000454
AC:
2
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.0000577
AC:
7

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:7Uncertain:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Jeune thoracic dystrophy Pathogenic:3
Jun 01, 2017
Dan Cohn Lab, University Of California Los Angeles
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:research

- -

Dec 24, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces threonine, which is neutral and polar, with alanine, which is neutral and non-polar, at codon 365 of the IFT80 protein (p.Thr365Ala). This variant is present in population databases (rs140202230, gnomAD 0.09%). This missense change has been observed in individual(s) with clinical features of short-rib polydactyly syndrome or asphyxiating thoracic dystrophy (PMID: 29068549; external communication, internal data). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 406217). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt IFT80 protein function with a negative predictive value of 95%. For these reasons, this variant has been classified as Pathogenic. -

-
University of Washington Center for Mendelian Genomics, University of Washington
Significance:Likely pathogenic
Review Status:no assertion criteria provided
Collection Method:research

- -

Type IV short rib polydactyly syndrome Pathogenic:2
Jun 01, 2017
Dan Cohn Lab, University Of California Los Angeles
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:research

- -

-
University of Washington Center for Mendelian Genomics, University of Washington
Significance:Likely pathogenic
Review Status:no assertion criteria provided
Collection Method:research

- -

not provided Pathogenic:1
Jan 14, 2025
GeneDx
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 30767363, 29068549) -

IFT80-related disorder Pathogenic:1
Jul 12, 2024
PreventionGenetics, part of Exact Sciences
Significance:Likely pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

The IFT80 c.1093A>G variant is predicted to result in the amino acid substitution p.Thr365Ala. This variant along with a second variant in the IFT80 gene has been reported in two patients with asphyxiating thoracic dystrophy and perinatal lethal short-rib polydactyly syndromes, respectively (Table S2, Zhang et al. 2018. PubMed ID: 29068549). This variant is reported in 0.092% of alleles in individuals of African descent in gnomAD. This variant is interpreted as likely pathogenic. -

Asphyxiating thoracic dystrophy 2 Uncertain:1
May 04, 2023
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The IFT80 c.1093A>G; p.Thr365Ala variant (rs140202230) was reported as compound heterozygous with another disease-associated variant in two individuals affected with short-rib polydactyly syndrome type IV or asphyxiating thoracic dystrophy (Zhang 2018). However, phasing was not confirmed in these reports. This variant is also reported in ClinVar (Variation ID: 406217) and is found in the general population with an overall allele frequency of 0.008% (23/282,476 alleles) in the Genome Aggregation Database. Computational analyses are uncertain whether this variant is neutral or deleterious (REVEL: 0.492). However, given the lack of clinical and functional data, the significance of the p.Thr365Ala variant is uncertain at this time. References: Zhang et al. Expanding the genetic architecture and phenotypic spectrum in the skeletal ciliopathies. Hum Mutat. 2018 Jan;39(1):152-166. PMID: 29068549. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.57
BayesDel_addAF
Benign
-0.014
T
BayesDel_noAF
Pathogenic
0.14
CADD
Pathogenic
27
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.60
D;.;.;.
Eigen
Pathogenic
0.71
Eigen_PC
Pathogenic
0.69
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Uncertain
0.96
D;.;D;D
M_CAP
Benign
0.069
D
MetaRNN
Benign
0.36
T;T;T;T
MetaSVM
Uncertain
0.25
D
MutationAssessor
Uncertain
2.2
M;.;.;.
PhyloP100
7.5
PrimateAI
Uncertain
0.78
T
PROVEAN
Uncertain
-4.3
D;D;D;D
REVEL
Uncertain
0.49
Sift
Uncertain
0.0060
D;D;D;D
Sift4G
Uncertain
0.060
T;T;T;D
Polyphen
1.0
D;.;.;.
Vest4
0.73
MVP
0.97
MPC
0.65
ClinPred
0.62
D
GERP RS
5.3
Varity_R
0.38
gMVP
0.73
Mutation Taster
=1/99
disease causing

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

Other links and lift over

dbSNP: rs140202230; hg19: chr3-160021761; API