chr3-52205873-G-A

Position:

• chr3-52205873-G-A

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_000688.6(ALAS1):​c.835G>A​(p.Gly279Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: ALAS1 NM_000688.6 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.86

Genes affected

ALAS1 (HGNC:396): (5'-aminolevulinate synthase 1) This gene encodes the mitochondrial enzyme which is catalyzes the rate-limiting step in heme (iron-protoporphyrin) biosynthesis. The enzyme encoded by this gene is the housekeeping enzyme; a separate gene encodes a form of the enzyme that is specific for erythroid tissue. The level of the mature encoded protein is regulated by heme: high levels of heme down-regulate the mature enzyme in mitochondria while low heme levels up-regulate. A pseudogene of this gene is located on chromosome 12. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Jan 2015]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.94

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
ALAS1	NM_000688.6	c.835G>A	p.Gly279Ser	missense_variant	7/12	ENST00000484952.6	NP_000679.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
ALAS1	ENST00000484952.6	c.835G>A	p.Gly279Ser	missense_variant	7/12	1	NM_000688.6	ENSP00000418779	P1
ALAS1	ENST00000310271.6	c.835G>A	p.Gly279Ser	missense_variant	6/11	1		ENSP00000309259	P1
ALAS1	ENST00000469224.5	c.835G>A	p.Gly279Ser	missense_variant	6/11	1		ENSP00000417719	P1
ALAS1	ENST00000394965.6	c.835G>A	p.Gly279Ser	missense_variant	7/12	2		ENSP00000378416	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

May 30, 2023

The c.835G>A (p.G279S) alteration is located in exon 7 (coding exon 5) of the ALAS1 gene. This alteration results from a G to A substitution at nucleotide position 835, causing the glycine (G) at amino acid position 279 to be replaced by a serine (S). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.97
BayesDel_addAF	Pathogenic	0.52	D
BayesDel_noAF	Pathogenic	0.51
CADD	Pathogenic	31
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.87	D;D;D;D
Eigen	Pathogenic	0.90
Eigen_PC	Pathogenic	0.89
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.98	.;.;.;D
M_CAP	Uncertain	0.28	D
MetaRNN	Pathogenic	0.94	D;D;D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Uncertain	2.1	M;M;M;M
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Pathogenic	0.84	D
PROVEAN	Pathogenic	-6.0	D;D;D;D
REVEL	Pathogenic	0.92
Sift	Uncertain	0.0010	D;D;D;D
Sift4G	Uncertain	0.0030	D;D;D;D
Polyphen		1.0	D;D;D;D
Vest4		0.92
MutPred		0.75		Gain of phosphorylation at G279 (P = 0.0754);Gain of phosphorylation at G279 (P = 0.0754);Gain of phosphorylation at G279 (P = 0.0754);Gain of phosphorylation at G279 (P = 0.0754);
MVP		0.97
MPC		0.81
ClinPred		0.99	D
GERP RS		5.8
Varity_R		0.86
gMVP		0.92

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr3-52239889;