chr20-48985590-A-G

Variant names:

• chr20-48985590-A-G
• rs770578384
• NM_006420.3:c.2253A>G

Variant summary

Our verdict is Benign. The variant received -10 ACMG points: 0P and 10B. BP4_Strong BP6 BP7 BS1

The NM_006420.3(ARFGEF2):​c.2253A>G​(p.Ala751Ala) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000725 in 1,614,122 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 Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000079 (0 hom.)
• Consequence: ARFGEF2 NM_006420.3 synonymous
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2 B:1
• Conservation: PhyloP100: -0.341
• Publications: 0 publications found

Genes affected

ARFGEF2 (HGNC:15853): (ADP ribosylation factor guanine nucleotide exchange factor 2) ADP-ribosylation factors (ARFs) play an important role in intracellular vesicular trafficking. The protein encoded by this gene is involved in the activation of ARFs by accelerating replacement of bound GDP with GTP and is involved in Golgi transport. It contains a Sec7 domain, which may be responsible for its guanine-nucleotide exchange activity and also brefeldin A inhibition. [provided by RefSeq, Jul 2008]

ARFGEF2 Gene-Disease associations (from GenCC):

• periventricular heterotopia with microcephaly, autosomal recessive

  Inheritance: AR Classification: STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), ClinGen
• periventricular nodular heterotopia

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Benign. The variant received -10 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.48).
• BP6: Variant 20-48985590-A-G is Benign according to our data. Variant chr20-48985590-A-G is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 210231.
• BP7: Synonymous conserved (PhyloP=-0.341 with no splicing effect.
• BS1: Variant frequency is greater than expected in population nfe. GnomAdExome4 allele frequency = 0.0000793 (116/1461884) while in subpopulation NFE AF = 0.0000989 (110/1112010). AF 95% confidence interval is 0.0000839. There are 0 homozygotes in GnomAdExome4. There are 53 alleles in the male GnomAdExome4 subpopulation. Median coverage is 32. This position passed quality control check.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_006420.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ARFGEF2	NM_006420.3	MANE Select	c.2253A>G	p.Ala751Ala	synonymous	Exon 16 of 39	NP_006411.2
	ARFGEF2	NM_001410846.1		c.2250A>G	p.Ala750Ala	synonymous	Exon 16 of 39	NP_001397775.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ARFGEF2	ENST00000371917.5	TSL:1 MANE Select	c.2253A>G	p.Ala751Ala	synonymous	Exon 16 of 39	ENSP00000360985.4
	ARFGEF2	ENST00000679436.1		c.2250A>G	p.Ala750Ala	synonymous	Exon 16 of 39	ENSP00000504888.1
	ARFGEF2	ENST00000681021.1		c.2253A>G	p.Ala751Ala	synonymous	Exon 16 of 38	ENSP00000505972.1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152238 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.0000358 AC: 9 AN: 251368 AF XY: 0.0000221

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000867

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.0000462

Gnomad NFE exome AF: 0.0000440

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000793 AC: 116 AN: 1461884 Hom.: 0 Cov.: 32 AF XY: 0.0000729 AC XY: 53 AN XY: 727244

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.0000671 AC: 3 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.0000374 AC: 2 AN: 53418

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5764

European-Non Finnish (NFE) AF: 0.0000989 AC: 110 AN: 1112010

Other (OTH) AF: 0.0000166 AC: 1 AN: 60394

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152238 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74370

African (AFR) AF: 0.00 AC: 0 AN: 41468

American (AMR) AF: 0.00 AC: 0 AN: 15284

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5200

South Asian (SAS) AF: 0.00 AC: 0 AN: 4828

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10622

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68044

Other (OTH) AF: 0.00 AC: 0 AN: 2094

Alfa AF: 0.0000282 Hom.: 0

Bravo AF: 0.0000189

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

ClinVar submissions as Germline

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
-	-	1	not provided (1)
-	1	-	not specified (1)
-	1	-	Periventricular heterotopia with microcephaly, autosomal recessive (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.48
CADD	Benign	6.8
DANN	Benign	0.61
PhyloP100		-0.34
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

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: rs770578384; hg19: chr20-47602127;