chr4-122923207-C-G

Position:

• chr4-122923207-C-G

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_145207.3(SPATA5):​c.65C>G​(p.Ser22Cys) 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 1,461,888 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/20 in silico tools predict a benign outcome for this variant. 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: 0.457

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 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.09724885).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SPATA5	NM_145207.3	c.65C>G	p.Ser22Cys	missense_variant	1/16	ENST00000274008.5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
AFG2A	ENST00000274008.5	c.65C>G	p.Ser22Cys	missense_variant	1/16	1	NM_145207.3	P1
AFG2A	ENST00000422835.2	n.107C>G		non_coding_transcript_exon_variant	1/15	1
AFG2A	ENST00000675612.1	c.65C>G	p.Ser22Cys	missense_variant	1/17
AFG2A	ENST00000674886.1	n.130C>G		non_coding_transcript_exon_variant	1/11

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461888 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727244

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

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

Apr 16, 2018

This sequence change replaces serine with cysteine at codon 22 of the SPATA5 protein (p.Ser22Cys). The serine residue is moderately conserved and there is a moderate physicochemical difference between serine and cysteine. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals with SPATA5-related disease. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The cysteine amino acid residue is found in multiple mammalian species, suggesting that this missense change does not adversely affect protein function. These predictions have not been confirmed by published functional studies and their clinical significance is uncertain. 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	0.086
BayesDel_addAF	Uncertain	0.048	T
BayesDel_noAF	Benign	-0.17
CADD	Benign	12
DANN	Uncertain	0.98
DEOGEN2	Benign	0.012	T
Eigen	Benign	-1.0
Eigen_PC	Benign	-1.1
FATHMM_MKL	Benign	0.027	N
LIST_S2	Benign	0.32	T
M_CAP	Benign	0.027	D
MetaRNN	Benign	0.097	T
MetaSVM	Uncertain	-0.15	T
MutationTaster	Benign	1.0	N
PrimateAI	Benign	0.44	T
PROVEAN	Benign	-0.98	N
REVEL	Benign	0.13
Sift	Uncertain	0.0030	D
Sift4G	Uncertain	0.0040	D
Polyphen		0.0020	B
Vest4		0.20
MutPred		0.24		Gain of glycosylation at S25 (P = 0.0175);
MVP		0.53
MPC		0.14
ClinPred		0.15	T
GERP RS		1.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.11
gMVP		0.17

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: rs1560780127; hg19: chr4-123844362; COSMIC: COSV56782397; COSMIC: COSV56782397;