rs121918011

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PM1PM5PP5_Very_Strong

The NM_000478.6(ALPL):​c.407G>A​(p.Arg136His) variant causes a missense change. The variant allele was found at a frequency of 0.000107 in 1,613,786 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. R136P) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.000059 ( 0 hom., cov: 33)
Exomes 𝑓: 0.00011 ( 0 hom. )

Consequence

ALPL
NM_000478.6 missense

Scores

3
11
5

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:19

Conservation

PhyloP100: 4.16
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]

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ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 12 ACMG points.

PM1
In a hotspot region, there are 7 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 2 benign, 5 uncertain in NM_000478.6
PM5
Other missense variant is known to change same aminoacid residue: Variant chr1-21563218-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 964572.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
PP5
Variant 1-21563219-G-A is Pathogenic according to our data. Variant chr1-21563219-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 13675.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr1-21563219-G-A is described in Lovd as [Likely_pathogenic]. Variant chr1-21563219-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
ALPLNM_000478.6 linkuse as main transcriptc.407G>A p.Arg136His missense_variant 5/12 ENST00000374840.8

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
ALPLENST00000374840.8 linkuse as main transcriptc.407G>A p.Arg136His missense_variant 5/121 NM_000478.6 P1P05186-1

Frequencies

GnomAD3 genomes
AF:
0.0000591
AC:
9
AN:
152198
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000482
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
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:
0.0000882
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.000136
AC:
34
AN:
250880
Hom.:
0
AF XY:
0.000125
AC XY:
17
AN XY:
135706
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000109
Gnomad SAS exome
AF:
0.0000980
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000256
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000112
AC:
163
AN:
1461588
Hom.:
0
Cov.:
37
AF XY:
0.000102
AC XY:
74
AN XY:
727102
show subpopulations
Gnomad4 AFR exome
AF:
0.0000299
Gnomad4 AMR exome
AF:
0.0000224
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.000101
Gnomad4 SAS exome
AF:
0.0000580
Gnomad4 FIN exome
AF:
0.0000188
Gnomad4 NFE exome
AF:
0.000132
Gnomad4 OTH exome
AF:
0.0000497
GnomAD4 genome
AF:
0.0000591
AC:
9
AN:
152198
Hom.:
0
Cov.:
33
AF XY:
0.0000538
AC XY:
4
AN XY:
74344
show subpopulations
Gnomad4 AFR
AF:
0.0000482
Gnomad4 AMR
AF:
0.0000654
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000882
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.000129
Hom.:
0
Bravo
AF:
0.0000831
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.000198
AC:
24
EpiCase
AF:
0.000218
EpiControl
AF:
0.000237

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:19
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Pathogenic:6
Pathogenic, no assertion criteria providedclinical testingMolecular Genetics Laboratory, BC Children's and BC Women's HospitalsJul 06, 2018- -
Pathogenic, criteria provided, single submitterclinical testingRevvity Omics, RevvityJun 08, 2020- -
Pathogenic, criteria provided, single submitterclinical testingGeneDxJun 16, 2023Published functional studies demonstrate a damaging effect as protein harboring the R136H variant has approximately 33% of the residual activity of wild-type protein (Zurutuza et al., 1999; Fauvert et al., 2009); Has also been reported as a single heterozygous variant in association with an odonto form and an adult form of hypophosphatasia (Fauvert et al., 2009; Michigami et al., 2019); In silico analysis, which includes splice predictors and evolutionary conservation, supports that this variant does not alter protein structure/function; This variant is associated with the following publications: (PMID: 22913777, 34712267, 34758253, 19500388, 11438998, 11855933, 11395499, 25023282, 10332035, 28506345, 26783040, 31600233, 31760938, 31707452, 29236161, 15694177, 10094560, 32160374, 34213743, 34189384, 31589614, 32956941, 33452237, 33549410, 35314707, 35726512) -
Pathogenic, criteria provided, single submitterclinical testingInvitaeJan 25, 2024This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 136 of the ALPL protein (p.Arg136His). This variant is present in population databases (rs121918011, gnomAD 0.02%). This missense change has been observed in individuals with hypophosphatasia (PMID: 10094560, 11438998, 11855933, 15694177, 19500388, 25731960, 26783040). This variant is also known as Arg119His. ClinVar contains an entry for this variant (Variation ID: 13675). 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 with a positive predictive value of 95%. Experimental studies have shown that this missense change affects ALPL function (PMID: 10332035, 19500388). This variant disrupts the p.Arg136 amino acid residue in ALPL. Other variant(s) that disrupt this residue have been observed in individuals with ALPL-related conditions (PMID: 19500388, 22913777, 24022022), which suggests that this may be a clinically significant amino acid residue. For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, criteria provided, single submitterclinical testingCeGaT Center for Human Genetics TuebingenJan 01, 2024ALPL: PM1, PM2, PM5, PS4:Moderate, PP4, PS3:Supporting -
Pathogenic, criteria provided, single submitterclinical testingARUP Laboratories, Molecular Genetics and Genomics, ARUP LaboratoriesJan 24, 2020The ALPL c.407G>A; p.Arg136His variant (rs121918011), also known as R119H, is reported in the literature in multiple individuals affected with hypophosphatasia, including many individuals who have another pathogenic variant on the opposite chromosome (Brun-Heath 2005, Cui 2012, Mumm 2002, Taillandier 1999, Taillandier 2001, Taillandier 2018, Taketani 2014, Whyte 2012, Whyte 2015). This variant is reported in ClinVar (Variation ID: 13675), and is found in the general population with an overall allele frequency of 0.013% (36/282262 alleles) in the Genome Aggregation Database. The arginine at codon 136 is moderately conserved, and computational analyses (SIFT: tolerated, PolyPhen-2: probably damaging) predict conflicting effects of this variant on protein structure/function. However, in vitro functional analyses demonstrate a significant reduction in protein activity (Fauvert 2009). Additionally, other amino acid substitutions at this codon (Cys, Leu, Pro) have been reported in individuals with hypophosphatasia (Cui 2012, Taillandier 2018, Yang 2013). Based on available information, this variant is considered to be pathogenic. References: Brun-Heath I et al. Characterization of 11 novel mutations in the tissue non-specific alkaline phosphatase gene responsible for hypophosphatasia and genotype-phenotype correlations. Mol Genet Metab. 2005 Mar;84(3):273-7. Cui Y et al. A systematic review of genetic skeletal disorders reported in Chinese biomedical journals between 1978 and 2012. Orphanet J Rare Dis. 2012 Aug 22;7:55. Fauvert D et al. Mild forms of hypophosphatasia mostly result from dominant negative effect of severe alleles or from compound heterozygosity for severe and moderate alleles. BMC Med Genet. 2009 Jun 6;10:51. Mumm S et al. Denaturing gradient gel electrophoresis analysis of the tissue nonspecific alkaline phosphatase isoenzyme gene in hypophosphatasia. Mol Genet Metab. 2002 Feb;75(2):143-53. Taillandier A et al. Characterization of eleven novel mutations (M45L, R119H, 544delG, G145V, H154Y, C184Y, D289V, 862+5A, 1172delC, R411X, E459K) in the tissue-nonspecific alkaline phosphatase (TNSALP) gene in patients with severe hypophosphatasia. Mutations in brief no. 217. Online. Hum Mutat. 1999;13(2):171-2. Taillandier A et al. Twelve novel mutations in the tissue-nonspecific alkaline phosphatase gene (ALPL) in patients with various forms of hypophosphatasia. Hum Mutat. 2001;18(1):83-4. Taillandier A et al. Genetic analysis of adults heterozygous for ALPL mutations. J Bone Miner Metab. 2018 Nov;36(6):723-733. Taketani T et al. Clinical and genetic aspects of hypophosphatasia in Japanese patients. Arch Dis Child. 2014 Mar;99(3):211-5. Whyte MP et al. Enzyme-replacement therapy in life-threatening hypophosphatasia. N Engl J Med. 2012 Mar 8;366(10):904-13. Whyte MP et al. Hypophosphatasia: validation and expansion of the clinical nosology for children from 25 years experience with 173 pediatric patients. Bone. 2015 Jun;75:229-39. Yang H et al. Characterization of six missense mutations in the tissue-nonspecific alkaline phosphatase (TNSALP) gene in Chinese children with hypophosphatasia. Cell Physiol Biochem. 2013;32(3):635-44. -
Adult hypophosphatasia Pathogenic:5
Pathogenic, criteria provided, single submitterclinical testingBaylor GeneticsMar 23, 2024- -
Pathogenic, criteria provided, single submitterclinical testingCenter of Genomic medicine, Geneva, University Hospital of GenevaJul 24, 2018- -
Likely pathogenic, no assertion criteria providedclinical testingGenomics England Pilot Project, Genomics England-- -
Pathogenic, criteria provided, single submitterclinical testingInstitute of Immunology and Genetics KaiserslauternJun 11, 2024ACMG Criteria: PS3, PS4, PM1, PM2, PM3, PM5, PP1, PP3, PP4, PP5; Variant was found in heterozygous state. -
Pathogenic, criteria provided, single submitterclinical testingCenter for Genomic Medicine, King Faisal Specialist Hospital and Research CenterMar 25, 2024- -
Hypophosphatasia Pathogenic:3
Pathogenic, criteria provided, single submitterclinical testingIllumina Laboratory Services, IlluminaApr 28, 2017The ALPL c.407G>A (p.Arg136His) missense variant has been reported in at least seven studies in which it is found in a compound heterozygous state in eight individuals with hypophosphatasia, including two with the infantile form, two with the childhood form, and four with mild symptoms, and in a heterozygous state in two individuals with the adult form of hypophosphatasia. The p.Arg136His variant was also found in a heterozygous state in two asymptomatic parents with low alkaline phosphatase activity and one asymptomatic individual with unknown alkaline phosphatase activity (Taillandier et al. 1998; Taillandier et al. 2001; Mumm et al. 2002; Brun-Heath et al. 2005; Fauvert et al. 2009; Cui et al. 2012; Riancho-Zarrabeitia et al. 2016). The p.Arg136His variant appears to be associated with more severe clinical symptoms when expressed in a compound heterozygous state with an additional ALPL variant. Control data are unavailable for this variant, which is reported at a frequency of 0.00030 in the European (non-Finnish) population of the Exome Aggregation Consortium. Functional studies demonstrated that the p.Arg136His variant protein displays one-third of the activity of the wild type alkaline phosphatase and does not have a dominant-negative effect when co-expressed with the wild type form (Zurutuza et al. 1999; Fauvert et al. 2009). Based on the collective evidence, the p.Arg136His variant is classified as pathogenic for hypophosphatasia. This variant was observed by ICSL as part of a predisposition screen in an ostensibly healthy population. -
Pathogenic, no assertion criteria providedclinical testingNatera, Inc.Sep 16, 2020- -
Pathogenic, criteria provided, single submitterclinical testingGenetics and Molecular Pathology, SA PathologyApr 21, 2021- -
Childhood hypophosphatasia Pathogenic:2
Pathogenic, no assertion criteria providedliterature onlyOMIMJun 01, 1999- -
Pathogenic, criteria provided, single submitterclinical testingBaylor GeneticsApr 22, 2019This variant was determined to be pathogenic according to ACMG Guidelines, 2015 [PMID:25741868]. -
Childhood hypophosphatasia;C0268412:Infantile hypophosphatasia;C0268413:Adult hypophosphatasia Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingFulgent Genetics, Fulgent GeneticsFeb 09, 2022- -
Osteogenesis imperfecta Pathogenic:1
Likely pathogenic, criteria provided, single submitterclinical testingGenome Diagnostics Laboratory, The Hospital for Sick ChildrenDec 16, 2019- -
Infantile hypophosphatasia Pathogenic:1
Pathogenic, no assertion criteria providedclinical testingCounsylDec 21, 2018- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.39
BayesDel_addAF
Uncertain
0.15
D
BayesDel_noAF
Pathogenic
0.27
CADD
Uncertain
25
DANN
Uncertain
0.98
DEOGEN2
Uncertain
0.67
D;.;.;D
Eigen
Uncertain
0.33
Eigen_PC
Uncertain
0.30
FATHMM_MKL
Uncertain
0.97
D
LIST_S2
Benign
0.84
.;T;T;T
M_CAP
Uncertain
0.17
D
MetaRNN
Uncertain
0.73
D;D;D;D
MetaSVM
Pathogenic
0.81
D
MutationAssessor
Uncertain
2.5
M;.;.;M
MutationTaster
Benign
1.0
A;A;A;A;A
PrimateAI
Uncertain
0.55
T
PROVEAN
Benign
-0.19
N;N;N;N
REVEL
Pathogenic
0.70
Sift
Benign
0.51
T;T;T;T
Sift4G
Benign
0.51
T;T;T;T
Polyphen
1.0
D;.;.;D
Vest4
0.59
MVP
0.97
MPC
1.4
ClinPred
0.16
T
GERP RS
4.3
Varity_R
0.11
gMVP
0.89

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs121918011; hg19: chr1-21889712; COSMIC: COSV66379441; API