chr4-123028316-A-G

Variant names:

• chr4-123028316-A-G
• rs998357703
• NM_145207.3:c.2000A>G

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM2 PP2 PP3_Strong

The NM_145207.3(AFG2A):​c.2000A>G​(p.Tyr667Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000479 in 1,461,856 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 Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. Y667H) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000048 (0 hom.)
• Consequence: AFG2A NM_145207.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 8.76
• Publications: 0 publications found

Genes affected

AFG2A (HGNC:18119): (AFG2 AAA ATPase homolog A) This gene encodes a member of the ATPase associated with diverse activities family, whose members are defined by a highly conserved ATPase domain. Members of this family participate in diverse cellular processes that include membrane fusion, DNA replication, microtubule severing, and protein degradation. The protein encoded by this gene has a putative mitochondrial targeting sequence and has been proposed to function in maintenance of mitochondrial function and integrity during mouse spermatogenesis. Allelic variants in this gene have been associated with epilepsy, hearing loss, and cognitive disability syndrome. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Sep 2016]

AFG2A Gene-Disease associations (from GenCC):

• microcephaly-intellectual disability-sensorineural hearing loss-epilepsy-abnormal muscle tone syndrome

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, PanelApp Australia, G2P, Labcorp Genetics (formerly Invitae)
• syndromic complex neurodevelopmental disorder

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen

ACMG classification

Our verdict: Likely_pathogenic. The variant received 7 ACMG points.

• 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 22 curated pathogenic missense variants (we use a threshold of 10). The gene has 7 curated benign missense variants. Gene score misZ: 0.46019 (below the threshold of 3.09). Trascript score misZ: 1.2041 (below the threshold of 3.09). GenCC associations: The gene is linked to microcephaly-intellectual disability-sensorineural hearing loss-epilepsy-abnormal muscle tone syndrome.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.96

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_145207.3. 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
	AFG2A	NM_145207.3	MANE Select	c.2000A>G	p.Tyr667Cys	missense	Exon 11 of 16	NP_660208.2	Q8NB90-1
	AFG2A	NM_001438322.1		c.2072A>G	p.Tyr691Cys	missense	Exon 12 of 17	NP_001425251.1
	AFG2A	NM_001437913.1		c.2069A>G	p.Tyr690Cys	missense	Exon 12 of 17	NP_001424842.1	A0A6Q8PGU6

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	AFG2A	ENST00000274008.5	TSL:1 MANE Select	c.2000A>G	p.Tyr667Cys	missense	Exon 11 of 16	ENSP00000274008.3	Q8NB90-1
	AFG2A	ENST00000422835.2	TSL:1	n.2042A>G		non_coding_transcript_exon	Exon 11 of 15
	AFG2A	ENST00000675612.1		c.2069A>G	p.Tyr690Cys	missense	Exon 12 of 17	ENSP00000502453.1	A0A6Q8PGU6

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000479 AC: 7 AN: 1461856 Hom.: 0 Cov.: 31 AF XY: 0.00000550 AC XY: 4 AN XY: 727228

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

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26132

East Asian (EAS) AF: 0.00 AC: 0 AN: 39690

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

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

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

European-Non Finnish (NFE) AF: 0.00000540 AC: 6 AN: 1111990

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

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	Microcephaly-intellectual disability-sensorineural hearing loss-epilepsy-abnormal muscle tone syndrome (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.22
BayesDel_addAF	Pathogenic	0.51	D
BayesDel_noAF	Pathogenic	0.50
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.72	D
Eigen	Pathogenic	0.87
Eigen_PC	Pathogenic	0.84
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.97	D
M_CAP	Pathogenic	0.47	D
MetaRNN	Pathogenic	0.96	D
MetaSVM	Pathogenic	1.0	D
PhyloP100		8.8
PrimateAI	Uncertain	0.74	T
PROVEAN	Pathogenic	-8.5	D
REVEL	Pathogenic	0.96
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0010	D
Polyphen		1.0	D
Vest4		0.89
MutPred		0.78		Loss of glycosylation at P670 (P = 0.0112)
MVP		0.97
MPC		0.71
ClinPred		1.0	D
GERP RS		5.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.90
gMVP		0.91
Mutation Taster		=47/53	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs998357703; hg19: chr4-123949471;