rs769948289

Variant summary

Our verdict is Pathogenic. The variant received 16 ACMG points: 16P and 0B. PVS1PP5_Very_Strong

The NM_000478.6(ALPL):​c.662delG​(p.Gly221ValfsTer56) variant causes a frameshift change. The variant allele was found at a frequency of 0.00000496 in 1,613,876 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000048 ( 0 hom. )

Consequence

ALPL
NM_000478.6 frameshift

Scores

Not classified

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:3

Conservation

PhyloP100: 5.19

Publications

1 publications found
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]
ALPL Gene-Disease associations (from GenCC):
  • adult hypophosphatasia
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, PanelApp Australia, Labcorp Genetics (formerly Invitae), Orphanet
  • childhood hypophosphatasia
    Inheritance: AR, AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: Laboratory for Molecular Medicine, ClinGen, Orphanet
  • hypophosphatasia
    Inheritance: AR Classification: DEFINITIVE Submitted by: Myriad Women’s Health, G2P
  • infantile hypophosphatasia
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, ClinGen, Labcorp Genetics (formerly Invitae), PanelApp Australia
  • odontohypophosphatasia
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • perinatal lethal hypophosphatasia
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 16 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PP5
Variant 1-21568111-TG-T is Pathogenic according to our data. Variant chr1-21568111-TG-T is described in ClinVar as Pathogenic. ClinVar VariationId is 996236.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
ALPLNM_000478.6 linkc.662delG p.Gly221ValfsTer56 frameshift_variant Exon 7 of 12 ENST00000374840.8 NP_000469.3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ALPLENST00000374840.8 linkc.662delG p.Gly221ValfsTer56 frameshift_variant Exon 7 of 12 1 NM_000478.6 ENSP00000363973.3
ALPLENST00000374832.5 linkc.662delG p.Gly221ValfsTer56 frameshift_variant Exon 7 of 12 2 ENSP00000363965.1
ALPLENST00000540617.5 linkc.497delG p.Gly166ValfsTer56 frameshift_variant Exon 6 of 11 2 ENSP00000442672.1
ALPLENST00000539907.5 linkc.431delG p.Gly144ValfsTer56 frameshift_variant Exon 5 of 10 2 ENSP00000437674.1

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
152050
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:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000795
AC:
2
AN:
251452
AF XY:
0.00000736
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000479
AC:
7
AN:
1461826
Hom.:
0
Cov.:
31
AF XY:
0.00000138
AC XY:
1
AN XY:
727212
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53384
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000540
AC:
6
AN:
1111986
Other (OTH)
AF:
0.00
AC:
0
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.482
Heterozygous variant carriers
0
1
2
2
3
4
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
AF:
0.00000658
AC:
1
AN:
152050
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74254
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41400
American (AMR)
AF:
0.00
AC:
0
AN:
15264
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5166
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4814
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10602
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68022
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.575
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000756

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Adult hypophosphatasia Pathogenic:1
Aug 10, 2023
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Hypophosphatasia Pathogenic:1
Aug 10, 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.662delG (p.Gly221ValfsX56) results in a premature termination codon, predicted to cause absence of the protein due to nonsense mediated decay, a commonly known mechanism for disease. The variant allele was found at a frequency of 8e-06 in 251452 control chromosomes (gnomAD). c.662delG has been reported in the literature as a compound heterozygous genotype in at least three individuals affected with autosomal recessive Hypophosphatasia, including at least one case with perinatal onset (e.g. Spentchian_2003, Glotov_2022). These data indicate that the variant is likely associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publications have been ascertained in the context of this evaluation (PMID: 33191482, 12815606, 36361766). One submitter has cited a clinical-significance assessment for this variant to ClinVar after 2014 and has classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

not provided Pathogenic:1
Feb 03, 2025
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.Gly221Valfs*56) in the ALPL gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in ALPL are known to be pathogenic (PMID: 3174660, 10679946, 32973344, 33814268). This variant is present in population databases (rs769948289, gnomAD 0.0009%). This premature translational stop signal has been observed in individual(s) with hypophosphatasia (PMID: 12815606). ClinVar contains an entry for this variant (Variation ID: 996236). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
PhyloP100
5.2
Mutation Taster
=0/200
disease causing (ClinVar)

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: rs769948289; hg19: chr1-21894604; COSMIC: COSV66377541; COSMIC: COSV66377541; API