rs772682471

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PM1PM5PP3_ModeratePP5_Very_Strong

The NM_000478.6(ALPL):​c.1183A>G​(p.Ile395Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000805 in 1,613,976 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 Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I395F) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000082 ( 0 hom. )

Consequence

ALPL
NM_000478.6 missense

Scores

6
7
6

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4

Conservation

PhyloP100: 7.24
Variant links:
Genes affected
ALPL (HGNC:438): (alkaline phosphatase, biomineralization associated) This gene encodes a member of the alkaline phosphatase family of proteins. There are at least four distinct but related alkaline phosphatases: intestinal, placental, placental-like, and liver/bone/kidney (tissue non-specific). The first three are located together on chromosome 2, while the tissue non-specific form is located on chromosome 1. The product of this gene is a membrane bound glycosylated enzyme that is not expressed in any particular tissue and is, therefore, referred to as the tissue-nonspecific form of the enzyme. Alternative splicing results in multiple transcript variants, at least one of which encodes a preproprotein that is proteolytically processed to generate the mature enzyme. This enzyme may play a role in bone mineralization. Mutations in this gene have been linked to hypophosphatasia, a disorder that is characterized by hypercalcemia and skeletal defects. [provided by RefSeq, Oct 2015]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 14 ACMG points.

PM1
In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 5 uncertain in NM_000478.6
PM5
Other missense variant is known to change same aminoacid residue: Variant chr1-21575919-T-C is described in ClinVar as [Pathogenic]. Clinvar id is 2202722.Status of the report is criteria_provided_single_submitter, 1 stars.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.881
PP5
Variant 1-21575918-A-G is Pathogenic according to our data. Variant chr1-21575918-A-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 1452498.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr1-21575918-A-G is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
ALPLNM_000478.6 linkc.1183A>G p.Ile395Val missense_variant Exon 10 of 12 ENST00000374840.8 NP_000469.3 P05186-1A0A024RAB4

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ALPLENST00000374840.8 linkc.1183A>G p.Ile395Val missense_variant Exon 10 of 12 1 NM_000478.6 ENSP00000363973.3 P05186-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152092
Hom.:
0
Cov.:
32
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:
0.000193
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:
0.0000199
AC:
5
AN:
251452
Hom.:
0
AF XY:
0.00000736
AC XY:
1
AN XY:
135904
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000116
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000821
AC:
12
AN:
1461884
Hom.:
0
Cov.:
32
AF XY:
0.00000688
AC XY:
5
AN XY:
727240
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.0000894
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000252
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000540
Gnomad4 OTH exome
AF:
0.0000166
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152092
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74296
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.000193
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.00000378
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Childhood hypophosphatasia;C0268412:Infantile hypophosphatasia;C0268413:Adult hypophosphatasia Pathogenic:1
Jul 29, 2021
Fulgent Genetics, Fulgent Genetics
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Adult hypophosphatasia Pathogenic:1
Mar 19, 2024
Baylor Genetics
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

not provided Pathogenic:1
Nov 21, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces isoleucine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 395 of the ALPL protein (p.Ile395Val). This variant is present in population databases (rs772682471, gnomAD 0.01%). This missense change has been observed in individual(s) with hypophosphatasia (PMID: 21713987, 31641588). ClinVar contains an entry for this variant (Variation ID: 1452498). 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 expected to disrupt ALPL protein function with a positive predictive value of 95%. Experimental studies have shown that this missense change affects ALPL function (PMID: 28586049). For these reasons, this variant has been classified as Pathogenic. -

Hypophosphatasia Pathogenic:1
Mar 31, 2023
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: ALPL c.1183A>G (p.Ile395Val) results in a conservative amino acid change in the encoded protein sequence. Three of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 2e-05 in 251452 control chromosomes (gnomAD). c.1183A>G has been reported in the literature in individuals affected with Hypophosphatasia, Autosomal Recessive (Wenkert_2011, Chen_2017, Yokoi_2019). These data indicate that the variant is likely to be associated with disease. Experimental evidence evaluating an impact on protein function demonstrated the variant affects ALP activity (Chen_2017). Two clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 and classified the variant as pathogenic/likely pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.12
BayesDel_addAF
Pathogenic
0.18
D
BayesDel_noAF
Pathogenic
0.25
CADD
Benign
23
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.72
D;.;.;D
Eigen
Uncertain
0.26
Eigen_PC
Uncertain
0.35
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Benign
0.85
.;D;D;D
M_CAP
Pathogenic
0.30
D
MetaRNN
Pathogenic
0.88
D;D;D;D
MetaSVM
Uncertain
0.75
D
MutationAssessor
Uncertain
2.3
M;.;.;M
PrimateAI
Uncertain
0.60
T
PROVEAN
Benign
-0.74
N;N;N;N
REVEL
Pathogenic
0.77
Sift
Benign
0.063
T;T;T;T
Sift4G
Benign
0.13
T;T;T;T
Polyphen
0.82
P;.;.;P
Vest4
0.83
MutPred
0.78
Gain of methylation at R391 (P = 0.1183);.;.;Gain of methylation at R391 (P = 0.1183);
MVP
0.97
MPC
0.68
ClinPred
0.65
D
GERP RS
4.9
Varity_R
0.25
gMVP
0.82

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

LitVar

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

Other links and lift over

dbSNP: rs772682471; hg19: chr1-21902411; API