1-21554105-G-A

Variant names:

• chr1-21554105-G-A
• NM_000478.6:c.24G>A

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Moderate BP6_Moderate BP7

The NM_000478.6(ALPL):​c.24G>A​(p.Leu8Leu) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,458,192 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★). Synonymous variant affecting the same amino acid position (i.e. L8L) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: ALPL NM_000478.6 synonymous
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: 1.18
• 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: ClinGen, Orphanet, Labcorp Genetics (formerly Invitae), PanelApp Australia
• ALPL-related autosomal dominant hypophosphatasia

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

  Inheritance: AD, AR Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Laboratory for Molecular Medicine, Orphanet
• 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), PanelApp Australia
• odontohypophosphatasia

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

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ENSG00000289715 (HGNC:):

ACMG classification

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.37).
• BP6: Variant 1-21554105-G-A is Benign according to our data. Variant chr1-21554105-G-A is described in ClinVar as Likely_benign. ClinVar VariationId is 2696584.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=1.18 with no splicing effect.

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.24G>A	p.Leu8Leu	synonymous	Exon 2 of 12	NP_000469.3
	ALPL	NM_001369803.2		c.24G>A	p.Leu8Leu	synonymous	Exon 2 of 12	NP_001356732.1	P05186-1
	ALPL	NM_001369804.2		c.24G>A	p.Leu8Leu	synonymous	Exon 2 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.24G>A	p.Leu8Leu	synonymous	Exon 2 of 12	ENSP00000363973.3	P05186-1
	ALPL	ENST00000374832.5	TSL:2	c.24G>A	p.Leu8Leu	synonymous	Exon 2 of 12	ENSP00000363965.1	P05186-1
	ALPL	ENST00000879459.1		c.24G>A	p.Leu8Leu	synonymous	Exon 1 of 10	ENSP00000549518.1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1458192 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 725456

African (AFR) AF: 0.00 AC: 0 AN: 33360

American (AMR) AF: 0.00 AC: 0 AN: 44600

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25986

East Asian (EAS) AF: 0.00 AC: 0 AN: 39470

South Asian (SAS) AF: 0.00 AC: 0 AN: 86218

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53054

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5672

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1109696

Other (OTH) AF: 0.00 AC: 0 AN: 60136

GnomAD4 genome Cov.: 31

ClinVar

ClinVar submissions as Germline

Significance: Likely benign

Revision: criteria provided, single submitter

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

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.37
CADD	Benign	9.8
DANN	Benign	0.83
PhyloP100		1.2
Mutation Taster		=100/0	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.10		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

hg19: chr1-21880598;