rs121918000

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PP3_StrongPP5_Very_Strong

The NM_000478.6(ALPL):​c.535G>A​(p.Ala179Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000479 in 1,461,742 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 (★★).

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0000048 ( 0 hom. )

Consequence

ALPL
NM_000478.6 missense

Scores

13
5
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:10

Conservation

PhyloP100: 9.55
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 12 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.993
PP5
Variant 1-21564103-G-A is Pathogenic according to our data. Variant chr1-21564103-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 13662.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr1-21564103-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
ALPLNM_000478.6 linkuse as main transcriptc.535G>A p.Ala179Thr missense_variant 6/12 ENST00000374840.8 NP_000469.3

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
ALPLENST00000374840.8 linkuse as main transcriptc.535G>A p.Ala179Thr missense_variant 6/121 NM_000478.6 ENSP00000363973 P1P05186-1

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD3 exomes
AF:
0.0000119
AC:
3
AN:
251074
Hom.:
0
AF XY:
0.0000221
AC XY:
3
AN XY:
135762
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 SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000264
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000479
AC:
7
AN:
1461742
Hom.:
0
Cov.:
32
AF XY:
0.00000825
AC XY:
6
AN XY:
727192
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000630
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
Cov.:
32

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:10
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Pathogenic:4
Pathogenic, criteria provided, single submitterclinical testingGeneDxMay 05, 2023Identified in patients with childhood hypophophatasia who harbored a second ALPL variant of unknown phase in published literature (Whyte et al., 2015; Genest et al., 2018); Reported in a heterozygous adult patient with features of hypophosphatasia in published literature (Schmidt et al., 2019); Published functional studies demonstrate a damaging effect on protein trafficking and enzyme activity (Weiss et al., 1988; Shibata et al., 1998; Di Mauro et al., 2002; Zhu et al., 2012); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; Also denoted as A162T due to alternative nomenclature; This variant is associated with the following publications: (PMID: 23509830, 9562633, 28991257, 23791648, 31400546, 3174660, 12162492, 11438998, 25731960, 29774402, 31485555, 32368696, 32160374) -
Pathogenic, criteria provided, single submitterclinical testingCeGaT Center for Human Genetics TuebingenOct 01, 2018- -
Pathogenic, criteria provided, single submitterclinical testingRevvity Omics, RevvityJan 06, 2022- -
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpMay 15, 2023For these reasons, this variant has been classified as Pathogenic. Experimental studies have shown that this missense change affects ALPL function (PMID: 9562633, 12162492, 23509830, 32160374). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt ALPL protein function. ClinVar contains an entry for this variant (Variation ID: 13662). This variant is also known as Ala162Thr. This missense change has been observed in individual(s) with clinical features of hypophosphatasia (PMID: 3174660, 11438998, 32160374; Invitae). This variant is present in population databases (rs121918000, gnomAD 0.003%). This sequence change replaces alanine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 179 of the ALPL protein (p.Ala179Thr). -
Infantile hypophosphatasia Pathogenic:2
Pathogenic, no assertion criteria providedliterature onlyOMIMOct 30, 2024- -
Likely pathogenic, criteria provided, single submitterliterature onlyCounsylAug 01, 2014- -
Hypophosphatasia Pathogenic:2
Pathogenic, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpAug 24, 2021Variant summary: ALPL c.535G>A (p.Ala179Thr) results in a non-conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 1.2e-05 in 251074 control chromosomes (gnomAD). c.535G>A has been reported in the literature in multiple compound heterozygous and homozygous individuals affected with Hypophosphatasia (e.g. Weiss_1988, Taillandier_2001, Whyte_2015, Seefried_2017, Del Angel_2020). These data indicate that the variant is very likely to be associated with disease. Experimental evidence obtained from multiple functional studies, demonstrated the variant causes a severe reduction in enzyme activity and affects its stability, transport and mineralisation ability (e.g. Weiss_1988, Fedde_1996, Di Mauro_2002, Zhu_2012, Del Angel_2020). A ClinVar submitter (evaluation after 2014) cites the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -
Pathogenic, no assertion criteria providedclinical testingNatera, Inc.Aug 25, 2020- -
Childhood hypophosphatasia;C0268412:Infantile hypophosphatasia;C0268413:Adult hypophosphatasia Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingFulgent Genetics, Fulgent GeneticsApr 26, 2022- -
Adult hypophosphatasia Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingBaylor GeneticsFeb 14, 2024- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.79
BayesDel_addAF
Pathogenic
0.52
D
BayesDel_noAF
Pathogenic
0.57
CADD
Pathogenic
26
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.97
D;.;.;D
Eigen
Pathogenic
0.78
Eigen_PC
Pathogenic
0.71
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.87
.;D;D;D
M_CAP
Pathogenic
0.54
D
MetaRNN
Pathogenic
0.99
D;D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
3.5
H;.;.;H
MutationTaster
Benign
1.0
A;A;A;A;A
PrimateAI
Uncertain
0.71
T
PROVEAN
Uncertain
-3.5
D;D;D;D
REVEL
Pathogenic
0.94
Sift
Uncertain
0.0010
D;D;D;D
Sift4G
Uncertain
0.025
D;D;D;D
Polyphen
0.85
P;.;.;P
Vest4
0.99
MutPred
0.98
Gain of glycosylation at A179 (P = 0.0474);.;.;Gain of glycosylation at A179 (P = 0.0474);
MVP
0.99
MPC
0.91
ClinPred
0.99
D
GERP RS
5.3
Varity_R
0.82
gMVP
0.98

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: rs121918000; hg19: chr1-21890596; COSMIC: COSV66379795; API