chr1-21577544-G-C

Variant names:

• chr1-21577544-G-C
• rs1413274209
• NM_000478.6:c.1471G>C

Variant summary

Our verdict is Pathogenic. The variant received 25 ACMG points: 25P and 0B. PS1_Very_Strong PM1 PM2 PP2 PP3_Strong PP5_Very_Strong

The NM_000478.6(ALPL):​c.1471G>C​(p.Gly491Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000688 in 1,453,674 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 Pathogenic (★★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Likely pathogenic in ClinVar.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: ALPL NM_000478.6 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 7.57
• Publications: 0 publications found

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: Orphanet, Labcorp Genetics (formerly Invitae), ClinGen
• ALPL-related autosomal dominant hypophosphatasia

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• childhood hypophosphatasia

  Inheritance: AD, AR Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, Laboratory for Molecular Medicine, ClinGen
• ALPL-related autosomal recessive hypophosphatasia

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• hypophosphatasia

  Inheritance: AR Classification: DEFINITIVE Submitted by: Myriad Women’s Health, G2P
• infantile hypophosphatasia

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, Orphanet, Labcorp Genetics (formerly Invitae)
• odontohypophosphatasia

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• perinatal lethal hypophosphatasia

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 25 ACMG points.

• PS1: Transcript NM_000478.6 (ALPL) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in ClinVar.
• PM1: In a hotspot region, there are 13 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 11 uncertain in NM_000478.6
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 220 curated pathogenic missense variants (we use a threshold of 10). The gene has 10 curated benign missense variants. Gene score misZ: 1.2672 (below the threshold of 3.09). Trascript score misZ: 1.9021 (below the threshold of 3.09). GenCC associations: The gene is linked to ALPL-related autosomal dominant hypophosphatasia, ALPL-related autosomal recessive hypophosphatasia, infantile hypophosphatasia, hypophosphatasia, adult hypophosphatasia, odontohypophosphatasia, childhood hypophosphatasia, perinatal lethal hypophosphatasia.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.985
• PP5: Variant 1-21577544-G-C is Pathogenic according to our data. Variant chr1-21577544-G-C is described in ClinVar as Pathogenic. ClinVar VariationId is 3713031.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000478.6. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ALPL	NM_000478.6	MANE Select	c.1471G>C	p.Gly491Arg	missense	Exon 12 of 12	NP_000469.3
	ALPL	NM_001369803.2		c.1471G>C	p.Gly491Arg	missense	Exon 12 of 12	NP_001356732.1	P05186-1
	ALPL	NM_001369804.2		c.1471G>C	p.Gly491Arg	missense	Exon 12 of 12	NP_001356733.1	P05186-1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ALPL	ENST00000374840.8	TSL:1 MANE Select	c.1471G>C	p.Gly491Arg	missense	Exon 12 of 12	ENSP00000363973.3	P05186-1
	ALPL	ENST00000374832.5	TSL:2	c.1471G>C	p.Gly491Arg	missense	Exon 12 of 12	ENSP00000363965.1	P05186-1
	ALPL	ENST00000879459.1		c.1351G>C	p.Gly451Arg	missense	Exon 10 of 10	ENSP00000549518.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.88e-7 AC: 1 AN: 1453674 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 723606

African (AFR) AF: 0.00 AC: 0 AN: 33472

American (AMR) AF: 0.00 AC: 0 AN: 44714

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26116

East Asian (EAS) AF: 0.00 AC: 0 AN: 39692

South Asian (SAS) AF: 0.00 AC: 0 AN: 86254

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 45544

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111780

Other (OTH) AF: 0.00 AC: 0 AN: 60334

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
1	-	-	Hypophosphatasia (1)
1	-	-	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.93
BayesDel_addAF	Pathogenic	0.50	D
BayesDel_noAF	Pathogenic	0.47
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.84	D
Eigen	Uncertain	0.38
Eigen_PC	Uncertain	0.37
FATHMM_MKL	Uncertain	0.89	D
LIST_S2	Uncertain	0.96	D
M_CAP	Pathogenic	0.67	D
MetaRNN	Pathogenic	0.98	D
MetaSVM	Pathogenic	0.93	D
MutationAssessor	Benign	0.69	N
PhyloP100		7.6
PrimateAI	Uncertain	0.75	T
PROVEAN	Benign	-1.2	N
REVEL	Pathogenic	0.80
Sift	Uncertain	0.0020	D
Sift4G	Uncertain	0.0040	D
Polyphen		1.0	D
Vest4		0.65
MutPred		0.92		Gain of methylation at G491 (P = 0.033)
MVP		0.98
MPC		1.4
ClinPred		0.95	D
GERP RS		4.6
Varity_R		0.36
gMVP		0.95
Mutation Taster		=0/100	disease causing

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

Other links and lift over

dbSNP: rs1413274209; hg19: chr1-21904037;