4-83462486-G-T

Variant names:

• chr4-83462486-G-T
• rs748616526
• NM_139076.3:c.1213C>A

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_139076.3(ABRAXAS1):​c.1213C>A​(p.Arg405Arg) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,460,208 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: ABRAXAS1 NM_139076.3 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 1.44

Genes affected

ABRAXAS1 (HGNC:25829): (abraxas 1, BRCA1 A complex subunit) This gene encodes a protein that binds to the C-terminal repeats of breast cancer 1 (BRCA1) through a phospho-SXXF motif. The encoded protein recruits ubiquitin interaction motif containing 1 protein to BRCA1 protein and is required for DNA damage resistance, DNA repair, and cell cycle checkpoint control. Pseudogenes of this gene are found on chromosomes 3 and 8. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Sep 2016]

MRPS18C (HGNC:16633): (mitochondrial ribosomal protein S18C) Mammalian mitochondrial ribosomal proteins are encoded by nuclear genes and help in protein synthesis within the mitochondrion. Mitochondrial ribosomes (mitoribosomes) consist of a small 28S subunit and a large 39S subunit. They have an estimated 75% protein to rRNA composition compared to prokaryotic ribosomes, where this ratio is reversed. Another difference between mammalian mitoribosomes and prokaryotic ribosomes is that the latter contain a 5S rRNA. Among different species, the proteins comprising the mitoribosome differ greatly in sequence, and sometimes in biochemical properties, which prevents easy recognition by sequence homology. This gene encodes a 28S subunit protein that belongs to the ribosomal protein S18P family. The encoded protein is one of three that has significant sequence similarity to bacterial S18 proteins. The primary sequences of the three human mitochondrial S18 proteins are no more closely related to each other than they are to the prokaryotic S18 proteins. Pseudogenes corresponding to this gene are found on chromosomes 8p, 12p, 15q, and 22q. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_benign. Variant got -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.78).
• BP7: Synonymous conserved (PhyloP=1.44 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
ABRAXAS1	NM_139076.3	c.1213C>A	p.Arg405Arg	synonymous_variant	Exon 9 of 9	ENST00000321945.12	NP_620775.2
MRPS18C	NM_016067.4	c.*1289G>T		downstream_gene_variant		ENST00000295491.9	NP_057151.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ABRAXAS1	ENST00000321945.12	c.1213C>A	p.Arg405Arg	synonymous_variant	Exon 9 of 9	1	NM_139076.3	ENSP00000369857.3
MRPS18C	ENST00000295491.9	c.*1289G>T		downstream_gene_variant		1	NM_016067.4	ENSP00000295491.4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000400 AC: 1 AN: 250012 Hom.: 0 AF XY: 0.00000740 AC XY: 1 AN XY: 135186

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 SAS exome AF: 0.00

Gnomad FIN exome AF: 0.0000465

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1460208 Hom.: 0 Cov.: 30 AF XY: 0.00000413 AC XY: 3 AN XY: 726384

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.0000562

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.78
CADD	Benign	1.6
DANN	Benign	0.52

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

LitVar

Other links and lift over

dbSNP: rs748616526; hg19: chr4-84383639;