2-46956927-G-T

Variant summary

Our verdict is Benign. The variant received -13 ACMG points: 0P and 13B. BP4_StrongBP6BS1BS2

The NM_020458.4(TTC7A):​c.437G>T​(p.Arg146Leu) variant causes a missense change. The variant allele was found at a frequency of 0.00636 in 1,614,206 control chromosomes in the GnomAD database, including 58 homozygotes. 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. R146W) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0046 ( 5 hom., cov: 33)
Exomes 𝑓: 0.0065 ( 53 hom. )

Consequence

TTC7A
NM_020458.4 missense

Scores

5
13

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3B:2

Conservation

PhyloP100: 3.62

Publications

7 publications found
Variant links:
Genes affected
TTC7A (HGNC:19750): (tetratricopeptide repeat domain 7A) This gene encodes a protein containing tetratricopeptide repeats. Mutations in this gene disrupt intestinal development and can cause early onset inflammatory bowel disease and intestinal atresia. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jun 2014]
TTC7A Gene-Disease associations (from GenCC):
  • gastrointestinal defects and immunodeficiency syndrome 1
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
  • multiple intestinal atresia
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, ClinGen, Ambry Genetics

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -13 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.008859396).
BP6
Variant 2-46956927-G-T is Benign according to our data. Variant chr2-46956927-G-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 458800.
BS1
Variant frequency is greater than expected in population nfe. GnomAd4 allele frequency = 0.00465 (708/152316) while in subpopulation NFE AF = 0.00701 (477/68030). AF 95% confidence interval is 0.00649. There are 5 homozygotes in GnomAd4. There are 357 alleles in the male GnomAd4 subpopulation. Median coverage is 33. This position passed quality control check.
BS2
High Homozygotes in GnomAd4 at 5 AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TTC7ANM_020458.4 linkc.437G>T p.Arg146Leu missense_variant Exon 3 of 20 ENST00000319190.11 NP_065191.2 Q9ULT0-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TTC7AENST00000319190.11 linkc.437G>T p.Arg146Leu missense_variant Exon 3 of 20 2 NM_020458.4 ENSP00000316699.5 Q9ULT0-1

Frequencies

GnomAD3 genomes
AF:
0.00465
AC:
707
AN:
152198
Hom.:
5
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00162
Gnomad AMI
AF:
0.0318
Gnomad AMR
AF:
0.00452
Gnomad ASJ
AF:
0.000576
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00270
Gnomad FIN
AF:
0.00386
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00700
Gnomad OTH
AF:
0.00478
GnomAD2 exomes
AF:
0.00484
AC:
1217
AN:
251492
AF XY:
0.00504
show subpopulations
Gnomad AFR exome
AF:
0.00135
Gnomad AMR exome
AF:
0.00142
Gnomad ASJ exome
AF:
0.000496
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00337
Gnomad NFE exome
AF:
0.00884
Gnomad OTH exome
AF:
0.00440
GnomAD4 exome
AF:
0.00654
AC:
9555
AN:
1461890
Hom.:
53
Cov.:
31
AF XY:
0.00643
AC XY:
4676
AN XY:
727248
show subpopulations
African (AFR)
AF:
0.00116
AC:
39
AN:
33480
American (AMR)
AF:
0.00145
AC:
65
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.000497
AC:
13
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00177
AC:
153
AN:
86258
European-Finnish (FIN)
AF:
0.00365
AC:
195
AN:
53420
Middle Eastern (MID)
AF:
0.000693
AC:
4
AN:
5768
European-Non Finnish (NFE)
AF:
0.00793
AC:
8815
AN:
1112012
Other (OTH)
AF:
0.00449
AC:
271
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.478
Heterozygous variant carriers
0
571
1143
1714
2286
2857
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
328
656
984
1312
1640
<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:
0.00465
AC:
708
AN:
152316
Hom.:
5
Cov.:
33
AF XY:
0.00479
AC XY:
357
AN XY:
74468
show subpopulations
African (AFR)
AF:
0.00161
AC:
67
AN:
41578
American (AMR)
AF:
0.00451
AC:
69
AN:
15300
Ashkenazi Jewish (ASJ)
AF:
0.000576
AC:
2
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5178
South Asian (SAS)
AF:
0.00270
AC:
13
AN:
4818
European-Finnish (FIN)
AF:
0.00386
AC:
41
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00701
AC:
477
AN:
68030
Other (OTH)
AF:
0.00473
AC:
10
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.502
Heterozygous variant carriers
0
36
71
107
142
178
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Genome Hom
Variant carriers
0
10
20
30
40
50
<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:
0.00116
Hom.:
6
Bravo
AF:
0.00425
TwinsUK
AF:
0.00809
AC:
30
ALSPAC
AF:
0.00856
AC:
33
ESP6500AA
AF:
0.00113
AC:
5
ESP6500EA
AF:
0.00721
AC:
62
ExAC
AF:
0.00572
AC:
694
EpiCase
AF:
0.00654
EpiControl
AF:
0.00569

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:3Benign:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Multiple gastrointestinal atresias Uncertain:1Benign:1
Aug 21, 2016
Mayo Clinic Laboratories, Mayo Clinic
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Feb 02, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Inborn genetic diseases Uncertain:1
Sep 01, 2021
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.437G>T (p.R146L) alteration is located in exon 3 (coding exon 3) of the TTC7A gene. This alteration results from a G to T substitution at nucleotide position 437, causing the arginine (R) at amino acid position 146 to be replaced by a leucine (L). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Gastrointestinal defects and immunodeficiency syndrome 1 Uncertain:1
Jun 14, 2021
Center for Genomics, Ann and Robert H. Lurie Children's Hospital of Chicago
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

TTC7A NM_020458.2 exon 3 p.Arg146Leu (c.437G>T): This variant has not been reported in the literature but is present in 0.6% (476/68038) of European alleles including 4 homozygotes in the Genome Aggregation Database (https://gnomad.broadinstitute.org/variant/2-46956927-G-T?dataset=gnomad_r3). This variant is present in ClinVar (Variation ID:458800). Evolutionary conservation and computational predictive tools for this variant are unclear. In summary, data on this variant is insufficient for disease classification. Therefore, the clinical significance of this variant is uncertain. -

not provided Benign:1
Dec 01, 2024
CeGaT Center for Human Genetics Tuebingen
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

TTC7A: BS2 -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.47
BayesDel_addAF
Benign
-0.33
T
BayesDel_noAF
Benign
-0.23
CADD
Benign
22
DANN
Uncertain
0.99
DEOGEN2
Benign
0.42
.;T;.
Eigen
Benign
-0.15
Eigen_PC
Benign
0.000018
FATHMM_MKL
Uncertain
0.89
D
LIST_S2
Benign
0.85
D;D;D
M_CAP
Benign
0.015
T
MetaRNN
Benign
0.0089
T;T;T
MetaSVM
Benign
-1.1
T
PhyloP100
3.6
PrimateAI
Uncertain
0.61
T
PROVEAN
Uncertain
-3.6
D;D;D
REVEL
Benign
0.20
Sift
Benign
0.14
T;T;D
Sift4G
Benign
0.088
T;T;T
Polyphen
0.0050
B;B;.
Vest4
0.48
MVP
0.31
MPC
0.092
ClinPred
0.025
T
GERP RS
4.9
Varity_R
0.27
gMVP
0.49
Mutation Taster
=90/10
polymorphism

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: rs61746139; hg19: chr2-47184066; API