chr4-123028279-C-G

Position:

• chr4-123028279-C-G

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_145207.3(SPATA5):​c.1963C>G​(p.Arg655Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,850 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: SPATA5 NM_145207.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.91

Genes affected

SPATA5 (HGNC:):

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SPATA5	NM_145207.3	c.1963C>G	p.Arg655Gly	missense_variant	11/16	ENST00000274008.5	NP_660208.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
AFG2A	ENST00000274008.5	c.1963C>G	p.Arg655Gly	missense_variant	11/16	1	NM_145207.3	ENSP00000274008	P1
AFG2A	ENST00000422835.2	n.2005C>G		non_coding_transcript_exon_variant	11/15	1
AFG2A	ENST00000675612.1	c.2032C>G	p.Arg678Gly	missense_variant	12/17			ENSP00000502453

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461850 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727222

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: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Microcephaly-intellectual disability-sensorineural hearing loss-epilepsy-abnormal muscle tone syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 31, 2021

This sequence change replaces arginine with glycine at codon 655 of the SPATA5 protein (p.Arg655Gly). The arginine residue is highly conserved and there is a moderate physicochemical difference between arginine and glycine. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals affected with SPATA5-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.19
BayesDel_addAF	Pathogenic	0.18	D
BayesDel_noAF	Uncertain	0.020
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Benign	0.23	T
Eigen	Uncertain	0.32
Eigen_PC	Uncertain	0.32
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Pathogenic	0.98	D
M_CAP	Pathogenic	0.29	D
MetaRNN	Uncertain	0.74	D
MetaSVM	Pathogenic	1.0	D
MutationTaster	Benign	0.99	D
PrimateAI	Benign	0.25	T
PROVEAN	Pathogenic	-6.5	D
REVEL	Uncertain	0.62
Sift	Uncertain	0.0020	D
Sift4G	Uncertain	0.0030	D
Polyphen		0.99	D
Vest4		0.48
MutPred		0.48		Loss of stability (P = 0.0208);
MVP		0.88
MPC		0.59
ClinPred		0.97	D
GERP RS		3.9
Varity_R		0.66
gMVP		0.70

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: rs763737752; hg19: chr4-123949434;