15-64963703-C-T

Position:

chr15-64963703-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_016630.7(SPG21):c.844G>A(p.Ala282Thr) variant causes a missense change. The variant allele was found at a frequency of 0.0000155 in 1,613,998 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/20 in silico tools predict a benign 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. A282V) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000016 ( 0 hom. )

Consequence

SPG21
NM_016630.7 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 4.47

Variant links:

Genes affected

SPG21 (HGNC:20373): (SPG21 abhydrolase domain containing, maspardin) The protein encoded by this gene binds to the hydrophobic C-terminal amino acids of CD4 which are involved in repression of T cell activation. The interaction with CD4 is mediated by the noncatalytic alpha/beta hydrolase fold domain of this protein. It is thus proposed that this gene product modulates the stimulatory activity of CD4. Mutations in this gene are associated with autosomal recessive spastic paraplegia 21 (SPG21), also known as mast syndrome. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Aug 2014]

SPG21 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

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=0.1763157).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE
SPG21	NM_016630.7 linkuse as main transcript	c.844G>A	p.Ala282Thr	missense_variant	9/9	ENST00000204566.7
SPG21	NM_001127889.5 linkuse as main transcript	c.844G>A	p.Ala282Thr	missense_variant	9/9
SPG21	NM_001127890.5 linkuse as main transcript	c.763G>A	p.Ala255Thr	missense_variant	8/8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SPG21	ENST00000204566.7 linkuse as main transcript	c.844G>A	p.Ala282Thr	missense_variant	9/9	1	NM_016630.7	P1	Q9NZD8-1

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152188

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

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

GnomAD3 exomes

AF:

0.0000159

AC:

AN:

251408

Hom.:

AF XY:

0.0000147

AC XY:

AN XY:

135882

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000289

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000544

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000176

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000157

AC:

AN:

1461810

Hom.:

Cov.:

AF XY:

0.00000963

AC XY:

AN XY:

727216

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000224

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.000176

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000135

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152188

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74346

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000108

Hom.:

Bravo

AF:

0.0000340

ExAC

AF:

0.0000165

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Mast syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jun 08, 2022

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. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C55"). This variant has not been reported in the literature in individuals affected with SPG21-related conditions. This variant is present in population databases (rs749945579, gnomAD 0.005%). This sequence change replaces alanine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 282 of the SPG21 protein (p.Ala282Thr). -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.21

BayesDel_addAF

Benign

-0.11

BayesDel_noAF

Benign

-0.23

CADD

Benign

DANN

Uncertain

0.99

DEOGEN2

Benign

0.15

T;.;T;.

Eigen

Benign

-0.32

Eigen_PC

Benign

-0.20

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Uncertain

0.95

.;D;D;D

M_CAP

Benign

0.0062

MetaRNN

Benign

0.18

T;T;T;T

MetaSVM

Benign

-1.1

MutationAssessor

Benign

0.69

N;.;N;.

MutationTaster

Benign

1.0

D;D;D;D

PrimateAI

Uncertain

0.70

PROVEAN

Benign

-0.35

N;N;N;N

REVEL

Benign

0.26

Sift

Benign

0.056

T;T;T;T

Sift4G

Benign

0.34

T;T;T;T

Polyphen

0.28

B;.;B;B

Vest4

0.45

MutPred

0.60

Gain of sheet (P = 0.0827);.;Gain of sheet (P = 0.0827);.;

MVP

0.23

MPC

0.36

ClinPred

0.18

GERP RS

3.9

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.1

Varity_R

0.063

gMVP

0.57

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.080

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over