3-3144683-A-G

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2PP3_Strong

The NM_182916.3(TRNT1):​c.581A>G​(p.Asp194Gly) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000043 in 1,394,926 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 0.0000043 ( 0 hom. )

Consequence

TRNT1
NM_182916.3 missense

Scores

15
3
1

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 9.11

Publications

0 publications found
Variant links:
Genes affected
TRNT1 (HGNC:17341): (tRNA nucleotidyl transferase 1) The protein encoded by this gene is a CCA-adding enzyme which belongs to the tRNA nucleotidyltransferase/poly(A) polymerase family. This essential enzyme functions by catalyzing the addition of the conserved nucleotide triplet CCA to the 3' terminus of tRNA molecules. Mutations in this gene result in sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Dec 2014]
CRBN (HGNC:30185): (cereblon) This gene encodes a protein related to the Lon protease protein family. In rodents and other mammals this gene product is found in the cytoplasm localized with a calcium channel membrane protein, and is thought to play a role in brain development. Mutations in this gene are associated with autosomal recessive nonsyndromic cognitive disability. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Mar 2010]
CRBN Gene-Disease associations (from GenCC):
  • intellectual disability
    Inheritance: AR Classification: MODERATE Submitted by: ClinGen
  • autosomal recessive non-syndromic intellectual disability
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • intellectual disability, autosomal recessive 2
    Inheritance: AR Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae), G2P

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.991

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TRNT1NM_182916.3 linkc.581A>G p.Asp194Gly missense_variant Exon 5 of 8 ENST00000251607.11 NP_886552.3 Q96Q11-1A0A024R2H7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TRNT1ENST00000251607.11 linkc.581A>G p.Asp194Gly missense_variant Exon 5 of 8 1 NM_182916.3 ENSP00000251607.6 Q96Q11-1

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD2 exomes
AF:
0.0000137
AC:
3
AN:
218660
AF XY:
0.00000839
show subpopulations
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000285
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000430
AC:
6
AN:
1394926
Hom.:
0
Cov.:
29
AF XY:
0.00000288
AC XY:
2
AN XY:
694476
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
30566
American (AMR)
AF:
0.00
AC:
0
AN:
34074
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
23996
East Asian (EAS)
AF:
0.00
AC:
0
AN:
38736
South Asian (SAS)
AF:
0.00
AC:
0
AN:
79062
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52226
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5464
European-Non Finnish (NFE)
AF:
0.00000559
AC:
6
AN:
1073272
Other (OTH)
AF:
0.00
AC:
0
AN:
57530
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.533
Heterozygous variant carriers
0
1
1
2
2
3
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
Cov.:
33
Alfa
AF:
0.0000282
Hom.:
0
Bravo
AF:
0.0000113
ExAC
AF:
0.00000825
AC:
1

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Congenital sideroblastic anemia-B-cell immunodeficiency-periodic fever-developmental delay syndrome Uncertain:1
Oct 19, 2020
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. This sequence change replaces aspartic acid with glycine at codon 194 of the TRNT1 protein (p.Asp194Gly). The aspartic acid residue is highly conserved and there is a moderate physicochemical difference between aspartic acid and glycine. This variant is present in population databases (rs754316396, ExAC 0.002%). This variant has not been reported in the literature in individuals with TRNT1-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
1.0
BayesDel_addAF
Pathogenic
0.45
D
BayesDel_noAF
Pathogenic
0.48
CADD
Pathogenic
29
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.63
D;.
Eigen
Pathogenic
1.1
Eigen_PC
Pathogenic
1.0
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
0.99
.;D
M_CAP
Pathogenic
0.58
D
MetaRNN
Pathogenic
0.99
D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
4.3
H;H
PhyloP100
9.1
PrimateAI
Uncertain
0.74
T
PROVEAN
Pathogenic
-6.9
D;D
REVEL
Pathogenic
0.96
Sift
Pathogenic
0.0
D;D
Sift4G
Pathogenic
0.0
D;D
Polyphen
1.0
D;D
Vest4
0.99
MutPred
0.93
Loss of stability (P = 0.0605);Loss of stability (P = 0.0605);
MVP
1.0
MPC
0.020
ClinPred
1.0
D
GERP RS
5.9
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.91
gMVP
0.98
Mutation Taster
=28/72
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.30
Details are displayed if max score is > 0.2
DS_DL_spliceai
0.30
Position offset: 27

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

Publications

Other links and lift over

dbSNP: rs754316396; hg19: chr3-3186367; API