chr18-26860795-T-A

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_001650.7(AQP4):​c.670A>T​(p.Met224Leu) variant causes a missense change. The variant allele was found at a frequency of 0.0000105 in 1,613,964 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000010 ( 0 hom. )

Consequence

AQP4
NM_001650.7 missense

Scores

1
5
13

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 5.95
Variant links:
Genes affected
AQP4 (HGNC:637): (aquaporin 4) This gene encodes a member of the aquaporin family of intrinsic membrane proteins that function as water-selective channels in the plasma membranes of many cells. This protein is the predominant aquaporin found in brain and has an important role in brain water homeostasis. Alternatively spliced transcript variants encoding different isoforms have been described for this gene. Additional isoforms, resulting from the use of alternative in-frame translation initiation codons, have also been described. Recent studies provided evidence for translational readthrough in this gene, and expression of C-terminally extended isoforms via the use of an alternative in-frame translation termination codon. [provided by RefSeq, Jun 2018]
AQP4-AS1 (HGNC:26399): (AQP4 antisense RNA 1)

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 0 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.22859794).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
AQP4NM_001650.7 linkuse as main transcriptc.670A>T p.Met224Leu missense_variant 4/5 ENST00000383168.9 NP_001641.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
AQP4ENST00000383168.9 linkuse as main transcriptc.670A>T p.Met224Leu missense_variant 4/51 NM_001650.7 ENSP00000372654 P1P55087-1

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152196
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000386
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
GnomAD3 exomes
AF:
0.00000795
AC:
2
AN:
251468
Hom.:
0
AF XY:
0.00000736
AC XY:
1
AN XY:
135912
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000103
AC:
15
AN:
1461768
Hom.:
0
Cov.:
31
AF XY:
0.00000825
AC XY:
6
AN XY:
727184
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.000378
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152196
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74356
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.000386
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.0000189
ExAC
AF:
0.0000165
AC:
2
Asia WGS
AF:
0.000289
AC:
1
AN:
3478

ClinVar

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

Submissions by phenotype

not specified Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingAmbry GeneticsFeb 05, 2024The c.670A>T (p.M224L) alteration is located in exon 4 (coding exon 4) of the AQP4 gene. This alteration results from a A to T substitution at nucleotide position 670, causing the methionine (M) at amino acid position 224 to be replaced by a leucine (L). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.15
BayesDel_addAF
Benign
-0.010
T
BayesDel_noAF
Uncertain
-0.080
CADD
Benign
23
DANN
Benign
0.96
DEOGEN2
Uncertain
0.59
D;.;.;T
Eigen
Benign
-0.042
Eigen_PC
Benign
0.20
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Uncertain
0.93
D;.;D;D
M_CAP
Benign
0.031
D
MetaRNN
Benign
0.23
T;T;T;T
MetaSVM
Uncertain
-0.069
T
MutationAssessor
Benign
-0.045
N;.;.;.
MutationTaster
Benign
1.0
D;D;D
PrimateAI
Uncertain
0.69
T
PROVEAN
Benign
-1.3
N;.;.;.
REVEL
Benign
0.27
Sift
Benign
0.32
T;.;.;.
Sift4G
Benign
0.52
T;T;T;.
Polyphen
0.0010
B;.;.;.
Vest4
0.45
MutPred
0.42
Loss of loop (P = 0.2237);.;.;.;
MVP
0.92
MPC
0.12
ClinPred
0.29
T
GERP RS
6.1
Varity_R
0.45
gMVP
0.62

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.080
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

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs371557672; hg19: chr18-24440759; API