11-66685810-C-T

Variant summary

Our verdict is Likely benign. Variant got -5 ACMG points: 0P and 5B. BP4_Strong BS1_Supporting

The NM_006946.4(SPTBN2):c.*61G>A variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000163 in 1,536,532 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 Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.00019 (0 hom., cov: 32)
  • Exomes 𝑓: 0.00016 (0 hom.)
• Consequence: SPTBN2 NM_006946.4 3_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -1.57

Genes affected

SPTBN2 (HGNC:11276): (spectrin beta, non-erythrocytic 2) Spectrins are principle components of a cell's membrane-cytoskeleton and are composed of two alpha and two beta spectrin subunits. The protein encoded by this gene (SPTBN2), is called spectrin beta non-erythrocytic 2 or beta-III spectrin. It is related to, but distinct from, the beta-II spectrin gene which is also known as spectrin beta non-erythrocytic 1 (SPTBN1). SPTBN2 regulates the glutamate signaling pathway by stabilizing the glutamate transporter EAAT4 at the surface of the plasma membrane. Mutations in this gene cause a form of spinocerebellar ataxia, SCA5, that is characterized by neurodegeneration, progressive locomotor incoordination, dysarthria, and uncoordinated eye movements. [provided by RefSeq, Dec 2009]

ACMG classification

Verdict is Likely_benign. Variant got -5 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.87).
• BS1: Variant frequency is greater than expected in population sas. gnomad4 allele frequency = 0.00019 (29/152338) while in subpopulation SAS AF= 0.00331 (16/4830). AF 95% confidence interval is 0.00208. There are 0 homozygotes in gnomad4. There are 18 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SPTBN2	NM_006946.4	c.*61G>A		3_prime_UTR_variant	38/38	ENST00000533211.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SPTBN2	ENST00000533211.6	c.*61G>A		3_prime_UTR_variant	38/38	5	NM_006946.4	P1
SPTBN2	ENST00000529997.5	c.*429G>A		3_prime_UTR_variant	35/35	5
SPTBN2	ENST00000528051.1	n.415G>A		non_coding_transcript_exon_variant	2/2	2
SPTBN2	ENST00000647510.2	c.*61G>A		3_prime_UTR_variant, NMD_transcript_variant	38/39

Frequencies

GnomAD3 genomes AF: 0.000191 AC: 29 AN: 152220 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: 0.00331

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.000191

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.000160 AC: 222 AN: 1384194 Hom.: 0 Cov.: 23 AF XY: 0.000202 AC XY: 140 AN XY: 692802

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000448

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000763

Gnomad4 SAS exome AF: 0.00163

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000670

Gnomad4 OTH exome AF: 0.000139

GnomAD4 genome AF: 0.000190 AC: 29 AN: 152338 Hom.: 0 Cov.: 32 AF XY: 0.000242 AC XY: 18 AN XY: 74498

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00331

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.000191

Gnomad4 OTH AF: 0.00

Alfa AF: 0.000424 Hom.: 0

Bravo AF: 0.0000642

Asia WGS AF: 0.000289 AC: 1 AN: 3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Autosomal dominant cerebellar ataxia Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jun 14, 2016

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.87
Cadd	Benign	0.67
Dann	Benign	0.75

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: rs566929715; hg19: chr11-66453281;