rs1557139920

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_000489.6(ATRX):​c.2304G>C​(p.Lys768Asn) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000182 in 1,097,474 control chromosomes in the GnomAD database, with no homozygous occurrence. There are 1 hemizygotes in GnomAD. In-silico tool predicts a benign outcome for this variant. 12/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. K768E) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 23)
Exomes 𝑓: 0.0000018 ( 0 hom. 1 hem. )

Consequence

ATRX
NM_000489.6 missense

Scores

5
11

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 0.647

Publications

0 publications found
Variant links:
Genes affected
ATRX (HGNC:886): (ATRX chromatin remodeler) The protein encoded by this gene contains an ATPase/helicase domain, and thus it belongs to the SWI/SNF family of chromatin remodeling proteins. This protein is found to undergo cell cycle-dependent phosphorylation, which regulates its nuclear matrix and chromatin association, and suggests its involvement in the gene regulation at interphase and chromosomal segregation in mitosis. Mutations in this gene are associated with X-linked syndromes exhibiting cognitive disabilities as well as alpha-thalassemia (ATRX) syndrome. These mutations have been shown to cause diverse changes in the pattern of DNA methylation, which may provide a link between chromatin remodeling, DNA methylation, and gene expression in developmental processes. Multiple alternatively spliced transcript variants encoding distinct isoforms have been reported. [provided by RefSeq, Jul 2017]
ATRX Gene-Disease associations (from GenCC):
  • alpha thalassemia-X-linked intellectual disability syndrome
    Inheritance: XL Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Labcorp Genetics (formerly Invitae), Orphanet, Ambry Genetics
  • ATR-X-related syndrome
    Inheritance: XL Classification: DEFINITIVE Submitted by: ClinGen
  • intellectual disability-hypotonic facies syndrome, X-linked, 1
    Inheritance: XL Classification: MODERATE Submitted by: Ambry Genetics

Genome browser will be placed here

ACMG classification

Classification was made for transcript

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

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.21425495).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
ATRXNM_000489.6 linkc.2304G>C p.Lys768Asn missense_variant Exon 9 of 35 ENST00000373344.11 NP_000480.3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ATRXENST00000373344.11 linkc.2304G>C p.Lys768Asn missense_variant Exon 9 of 35 1 NM_000489.6 ENSP00000362441.4

Frequencies

GnomAD3 genomes
Cov.:
23
GnomAD4 exome
AF:
0.00000182
AC:
2
AN:
1097474
Hom.:
0
Cov.:
33
AF XY:
0.00000276
AC XY:
1
AN XY:
362902
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.0000758
AC:
2
AN:
26382
American (AMR)
AF:
0.00
AC:
0
AN:
35204
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
19374
East Asian (EAS)
AF:
0.00
AC:
0
AN:
30191
South Asian (SAS)
AF:
0.00
AC:
0
AN:
54122
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
40520
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
4123
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
841485
Other (OTH)
AF:
0.00
AC:
0
AN:
46073
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.375
Heterozygous variant carriers
0
0
1
1
2
2
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.:
23
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000113

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Inborn genetic diseases Uncertain:1
Jul 25, 2017
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Alpha thalassemia-X-linked intellectual disability syndrome Uncertain:1
Aug 17, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces lysine, which is basic and polar, with asparagine, which is neutral and polar, at codon 768 of the ATRX protein (p.Lys768Asn). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with ATRX-related conditions. ClinVar contains an entry for this variant (Variation ID: 521943). 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 ATRX protein function with a negative predictive value of 95%. 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.22
BayesDel_addAF
Benign
-0.13
T
BayesDel_noAF
Benign
-0.42
CADD
Benign
16
DANN
Benign
0.96
DEOGEN2
Benign
0.015
.;.;T;T
FATHMM_MKL
Benign
0.34
N
LIST_S2
Uncertain
0.90
D;.;D;D
M_CAP
Uncertain
0.26
D
MetaRNN
Benign
0.21
T;T;T;T
MetaSVM
Uncertain
0.092
D
PhyloP100
0.65
PrimateAI
Benign
0.45
T
PROVEAN
Benign
-0.87
N;N;.;.
REVEL
Uncertain
0.29
Sift
Uncertain
0.0010
D;D;.;.
Sift4G
Benign
0.41
T;T;T;.
Polyphen
0.75
P;.;.;.
Vest4
0.082
MutPred
0.16
Loss of ubiquitination at K768 (P = 0.0116);.;.;.;
MVP
0.84
MPC
0.083
ClinPred
0.57
D
GERP RS
1.1
gMVP
0.15
Mutation Taster
=96/4
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: rs1557139920; hg19: chrX-76938444; COSMIC: COSV64874006; COSMIC: COSV64874006; API