rs387906525

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PVS1_ModeratePP5_Very_Strong

The NM_000478.6(ALPL):​c.1559delT​(p.Leu520ArgfsTer86) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000206 in 1,598,412 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000021 ( 0 hom. )

Consequence

ALPL
NM_000478.6 frameshift

Scores

Not classified

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:8O:1

Conservation

PhyloP100: 0.754
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 10 ACMG points.

PVS1
Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.0102 CDS is truncated, and there are 0 pathogenic variants in the truncated region.
PP5
Variant 1-21577631-CT-C is Pathogenic according to our data. Variant chr1-21577631-CT-C is described in ClinVar as [Pathogenic]. Clinvar id is 13674.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr1-21577631-CT-C is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
ALPLNM_000478.6 linkc.1559delT p.Leu520ArgfsTer86 frameshift_variant Exon 12 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.1559delT p.Leu520ArgfsTer86 frameshift_variant Exon 12 of 12 1 NM_000478.6 ENSP00000363973.3 P05186-1

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152246
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:
0.000385
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:
0.00000866
AC:
2
AN:
230820
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
127334
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000114
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000214
AC:
31
AN:
1446166
Hom.:
0
Cov.:
33
AF XY:
0.0000194
AC XY:
14
AN XY:
719910
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.000758
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
9.00e-7
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152246
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74378
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.000385
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.00000378

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:8Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Pathogenic:3
Jul 01, 2024
GeneDx
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Published functional studies demonstrate a damaging effect with failure to localize to the cell surface and failure to rescue mineralization (PMID: 7833929, 9814472, 15794757); Frameshift variant predicted to result in abnormal protein length as the last 4 amino acids are replaced with 85 different amino acids; This variant is associated with the following publications: (PMID: 36217348, 32160374, 15794757, 9814472, 7833929, 24334170, 28802630, 29160033, 31014398, 30083035, 31707452, 31600233, 31641588, 31857675, 31787692, 23926372, 18455459, 15660230, 32547926, 33452237, 11810413, 12975786, 35024386, 35197081) -

Aug 28, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Leu520Argfs*86) in the ALPL gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 5 amino acid(s) of the ALPL protein. This variant is present in population databases (rs387906525, gnomAD 0.01%). This premature translational stop signal has been observed in individual(s) with hypophosphatasia (PMID: 7833929, 9814472, 15660230, 24334170, 28802630). This variant is also known as delT1735. ClinVar contains an entry for this variant (Variation ID: 13674). Algorithms developed to predict the effect of variants on gene product structure and function are not available or were not evaluated for this variant. Experimental studies have shown that this premature translational stop signal affects ALPL function (PMID: 9814472, 15660230, 15794757). For these reasons, this variant has been classified as Pathogenic. -

Oct 14, 2014
Eurofins Ntd Llc (ga)
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Hypophosphatasia Pathogenic:2Other:1
May 14, 2021
Natera, Inc.
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

-
GeneReviews
Significance: not provided
Review Status: no classification provided
Collection Method: literature only

- -

Feb 24, 2020
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.1559delT (p.Leu520ArgfsX86) causes a frameshift which results in an extension of the protein. The variant allele was found at a frequency of 8.7e-06 in 230820 control chromosomes (genomAD). In Japanese HPP, this variant is the most frequent mutation (Komaru_2005, Michigami_2019, Okawa_2019). c.1559delT has been reported in the literature in compound heterozygous and homozygous individuals affected with Hypophosphatasia (Okawa_2019, Koyama_2019). These data indicate that the variant is very likely to be associated with disease. At least one functional study reports this variant effect results in decreasing normal activity (Komaru_2005). One ClinVar submitter (evaluation after 2014) cites the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Infantile hypophosphatasia Pathogenic:2
Dec 26, 2019
Myriad Genetics, Inc.
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

NM_000478.4(ALPL):c.1559delT(L520Rfs*86) is classified as pathogenic in the context of hypophosphatasia. Sources cited for classification include the following: PMID 23926372, 9452105, 15660230, 18455459, 15660230 and 15794757. Classification of NM_000478.4(ALPL):c.1559delT(L520Rfs*86) is based on the following criteria: This is a well-established pathogenic variant in the literature that has been observed more frequently in patients with clinical diagnoses than in healthy populations. Please note: this variant was assessed in the context of healthy population screening. -

Dec 01, 1998
OMIM
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: literature only

- -

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

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction

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: rs387906525; hg19: chr1-21904124; API